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In
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UCT
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ca
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b
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s
u
b
j
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p
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d
eb
ate
[
1
]
an
d
w
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m
ak
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t
h
e
s
tu
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e
n
ts
a
w
ar
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is
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ar
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o
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e
[
2
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r
ef
le
cted
b
y
t
h
e
g
r
o
w
t
h
i
n
citize
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r
esp
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iv
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u
ed
in
th
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f
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m
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f
citizen
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[
3
]
.
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u
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ak
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as th
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f
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citize
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[
4
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.
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m
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ti
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ti
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liter
a
c
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5
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elo
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[
6
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,
[
7
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an
d
all
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d
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to
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as a
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citize
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[
6
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1
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A
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I
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2
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I
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Vo
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Dec
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2
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1
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:
271
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3
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1
1
]
.
L
i
k
e
w
is
e,
Z
eid
ler
an
d
Nico
l
s
(
2
0
0
9
)
as
cited
b
y
A
li
g
ae
n
(
2
0
1
2
)
p
o
in
ted
o
u
t
th
at
en
g
a
g
i
n
g
s
t
u
d
en
t
s
in
SS
I
is
p
er
s
o
n
all
y
m
ea
n
in
g
f
u
l
an
d
e
n
g
ag
i
n
g
t
h
at
r
eq
u
ir
es
th
e
u
s
e
o
f
ev
id
en
ce
-
b
ased
r
ea
s
o
n
in
g
an
d
p
r
o
v
id
e
a
co
n
tex
t
f
o
r
u
n
d
er
s
ta
n
d
in
g
s
cie
n
ti
f
ic
i
n
f
o
r
m
atio
n
[
1
2
]
.
2.
RE
S
E
ARCH
M
E
T
H
O
D
T
h
is
s
tu
d
y
u
til
ized
q
u
alitati
v
e
m
et
h
o
d
o
f
r
esear
ch
p
ar
ticu
lar
l
y
p
ar
ticip
ato
r
y
ac
tio
n
r
esear
ch
(
P
A
R
)
to
in
v
e
s
ti
g
ate
h
o
w
s
t
u
d
en
ts
‟
w
o
r
k
w
it
h
s
o
cio
-
s
cien
ti
f
ic
is
s
u
e
s
i
n
th
e
to
p
ic
s
o
u
r
ce
s
o
f
en
er
g
y
i
n
P
h
y
s
ical
Scie
n
ce
class
(
T
r
an
s
f
o
r
m
ati
v
e
L
ea
r
n
i
n
g
)
.
L
i
k
e
w
i
s
e,
P
AR
w
as
e
m
p
lo
y
ed
b
ec
au
s
e
it
i
n
v
o
lv
e
s
m
o
r
e
d
o
cu
m
e
n
ti
n
g
ca
r
ef
u
ll
y
a
n
d
r
ec
o
r
d
in
g
ac
tio
n
an
d
w
h
at
p
eo
p
le
th
i
n
k
ab
o
u
t
it
in
w
a
y
s
o
th
er
s
f
o
u
n
d
ac
ce
s
s
ib
le
[
1
3
]
.
M
o
r
eo
v
er
,
P
A
R
o
f
f
er
s
a
p
o
w
er
f
u
l
a
n
d
e
m
p
o
w
er
i
n
g
ap
p
r
o
ac
h
to
ed
u
ca
tio
n
al
e
v
al
u
atio
n
i
n
w
h
ic
h
th
er
e
is
a
n
ac
tiv
e
p
ar
tn
er
s
h
ip
b
et
w
ee
n
r
esear
c
h
e
r
s
an
d
r
esear
ch
ed
.
T
w
o
h
u
n
d
r
ed
t
w
en
t
y
s
tu
d
e
n
ts
w
h
o
co
m
p
r
is
ed
t
h
e
f
i
v
e
s
ec
t
i
o
n
s
o
f
b
u
s
i
n
e
s
s
co
u
r
s
es
o
f
D
e
L
a
Salle
L
ip
a
e
n
r
o
lled
in
P
h
y
s
ical
Sc
ie
n
ce
(
T
r
an
s
f
o
r
m
a
tiv
e
L
ea
r
n
i
n
g
C
las
s
)
d
u
r
i
n
g
t
h
e
S
ec
o
n
d
Se
m
ester
Sch
o
o
l
Yea
r
2012
–
2
0
1
3
w
er
eth
e
p
ar
ticip
a
n
ts
o
f
t
h
i
s
s
tu
d
y
w
it
h
th
e
r
e
s
ea
r
ch
er
as
t
h
e
o
n
e
co
n
d
u
cti
n
g
t
h
e
le
s
s
o
n
w
h
ile
o
b
s
er
v
in
g
th
e
m
.
An
in
ter
v
ie
w
g
u
id
e
w
as
co
n
s
tr
u
cted
to
in
v
e
s
tig
a
te
h
o
w
s
t
u
d
en
ts
‟
w
o
r
k
with
s
o
cio
-
s
cie
n
ti
f
ic
is
s
u
es
i
n
t
h
e
to
p
ic
s
o
u
r
ce
s
o
f
en
er
g
y
i
n
P
h
y
s
ical
Scie
n
ce
cl
ass
(
T
r
an
s
f
o
r
m
a
tiv
e
L
e
ar
n
in
g
)
.
L
ik
e
w
i
s
e,
d
o
cu
m
en
tar
y
an
al
y
s
is
(
j
o
u
r
n
al
w
r
iti
n
g
)
,
o
b
s
er
v
atio
n
an
d
tr
ian
g
u
lat
io
n
o
f
d
ata
w
ill
b
e
co
n
s
id
er
ed
i
n
t
h
e
co
llectio
n
o
f
d
ata.
R
esp
o
n
s
es
o
f
s
t
u
d
en
t
s
in
t
h
e
i
n
ter
v
ie
w
g
u
i
d
e
w
er
e
an
al
y
ze
d
u
s
i
n
g
ax
ial
co
d
in
g
tech
n
iq
u
e
in
w
h
ic
h
co
d
es
o
r
th
e
m
es
w
er
e
g
en
er
ated
an
d
r
elate
d
to
o
n
e
an
o
th
er
.
T
h
is
s
t
u
d
y
in
v
o
l
v
ed
co
n
tin
u
i
n
g
s
p
ir
al
o
f
p
lan
n
i
n
g
,
ac
tin
g
,
o
b
s
er
v
i
n
g
,
r
e
f
lecti
n
g
an
d
th
e
n
r
e
-
p
la
n
n
in
g
a
n
d
s
o
r
o
u
n
d
th
e
s
p
ir
al
a
g
ain
[
1
4
]
.
2
.
1
.
P
la
nn
ing
T
h
e
r
esear
ch
er
p
lan
n
ed
o
n
wh
at
SS
I
w
i
ll
b
e
g
i
v
en
to
t
h
e
p
ar
ticip
an
ts
b
ased
o
n
Sc
h
o
o
l
an
d
So
cial
I
s
s
u
e
s
Mo
d
el
f
o
r
T
ea
ch
in
g
SS
I
[
3
]
w
h
ich
co
n
s
id
er
s
h
ier
ar
ch
y
(
s
c
ien
t
is
t/
teac
h
er
s
-
s
tu
d
e
n
t)
;
s
o
u
r
ce
o
f
k
n
o
w
led
g
e
(
co
r
p
u
s
o
f
s
cie
n
ce
an
d
o
th
er
d
is
cip
lin
e
s
)
;
v
ie
w
o
f
k
n
o
w
led
g
e
(
s
cie
n
ce
to
b
e
k
n
o
w
n
i
s
co
r
r
ec
t
b
u
t
th
e
e
m
p
h
a
s
is
is
o
n
th
e
m
e
th
o
d
s
an
d
p
r
o
ce
d
u
r
es
o
f
s
c
ien
ce
r
ath
er
t
h
an
f
ac
t
s
.
Scie
n
ce
d
i
f
f
u
s
e
s
o
u
t
i
n
to
s
o
cial
ap
p
licatio
n
s
b
u
t
th
er
e
i
s
s
o
m
e
tr
an
s
p
ar
en
c
y
ab
o
u
t
th
e
s
cie
n
t
if
ic
p
r
o
ce
s
s
)
;
co
n
tr
o
v
er
s
y
(
tak
es
p
lace
w
it
h
i
n
t
h
e
class
r
o
o
m
b
u
t
m
i
g
h
t
i
n
v
o
l
v
e
an
al
y
zi
n
g
s
cie
n
ce
i
n
n
e
wsp
ap
er
s
d
is
ti
n
g
u
is
h
i
n
g
r
h
e
to
r
ic
f
r
o
m
ev
id
en
ce
)
;
p
ed
ag
o
g
y
(
teac
h
er
co
n
tr
o
ls
co
n
ten
t
b
u
t
m
i
g
h
t
b
e
a
f
ac
ilit
ato
r
in
d
is
cu
s
s
io
n
)
;
an
d
ass
ess
m
e
n
t
(
test
s
ar
g
u
m
e
n
tatio
n
ab
ili
ties
,
u
s
e
o
f
w
ar
r
an
t
s
to
s
u
p
p
o
r
t c
lai
m
s
)
.
L
i
k
e
w
is
e,
t
h
e
teac
h
er
-
r
esear
c
h
er
co
n
s
id
er
ed
s
o
m
e
ch
ar
ac
ter
is
tic
s
o
f
SS
I
as
e
n
u
m
er
ated
b
y
R
ad
clif
f
e
&
Gr
ac
e
(
2
0
0
3
)
as
cited
b
y
E
k
b
o
r
g
&
Ottan
d
er
(
2
0
0
6
)
as:
th
e
y
ar
e
i
m
p
o
r
tan
t
f
o
r
s
o
ciet
y
,
h
a
v
e
a
b
asi
s
f
o
r
s
cie
n
ce
,
in
v
o
l
v
e
f
o
r
m
i
n
g
o
p
i
n
io
n
s
,
ar
e
f
r
eq
u
en
tl
y
m
ed
ia
r
ep
o
r
ted
,
ad
d
r
ess
lo
ca
l,
n
atio
n
al
an
d
g
lo
b
al
d
i
m
en
s
io
n
s
w
it
h
atte
n
d
an
t
p
o
liti
ca
l
a
n
d
s
o
cieta
l
f
r
a
m
e
w
o
r
k
,
in
v
o
l
v
e
v
alu
e
s
a
n
d
eth
ical
r
ea
s
o
n
i
n
g
,
m
a
y
in
v
o
l
v
e
co
n
s
id
er
atio
n
o
f
s
u
s
tai
n
ab
le
d
ev
elo
p
m
en
t
a
n
d
m
a
y
r
eq
u
ir
e
s
o
m
e
u
n
d
er
s
ta
n
d
in
g
o
f
p
r
o
b
ab
ilit
y
a
n
d
r
is
k
s
an
d
t
h
er
e
ar
e
“
n
o
r
ig
h
t”
an
s
w
er
s
.
2
.
2
.
Act
ing
Af
ter
t
h
e
r
esear
ch
er
h
ad
c
h
o
s
e
n
th
e
i
s
s
u
e
o
n
s
o
u
r
ce
s
o
f
e
n
er
g
y
,
t
h
e
r
esear
ch
er
d
is
c
u
s
s
ed
th
e
co
n
ten
t
s
o
f
th
e
les
s
o
n
a
n
d
i
n
teg
r
ated
S
SI.
T
h
e
r
esear
ch
er
g
r
o
u
p
ed
s
t
u
d
en
t
s
to
s
h
ar
e
t
h
eir
ar
g
u
m
en
ta
tio
n
b
ased
o
n
th
e
g
u
id
e
q
u
e
s
tio
n
s
f
o
r
t
h
e
s
aid
ac
tiv
it
y
.
2
.
3
.
O
bs
er
v
ing
W
h
ile
p
ar
ticip
an
ts
w
er
e
in
v
o
l
v
ed
in
g
r
o
u
p
d
is
c
u
s
s
io
n
,
t
h
e
r
esear
ch
er
o
b
s
er
v
ed
w
h
at
w
i
l
l
tr
an
s
p
ir
e
d
u
r
in
g
th
e
ar
g
u
m
e
n
tatio
n
.
No
t
e
-
ta
k
in
g
w
as d
o
n
e
i
n
t
h
e
p
r
o
ce
s
s
.
2
.
4
.
Ref
lect
ing
P
ar
ticip
an
ts
w
er
e
r
eq
u
ir
ed
to
w
r
ite
a
n
d
s
u
b
m
it
a
r
e
f
lectio
n
an
d
f
o
cu
s
g
r
o
u
p
in
ter
v
ie
w
w
as
co
n
d
u
cted
o
n
ex
p
er
ien
ce
s
o
f
n
o
n
-
m
aj
o
r
s
in
u
s
i
n
g
S
SI
in
lear
n
in
g
s
o
u
r
ce
s
o
f
en
er
g
y
.
2
.
5
.
Re
-
pla
nn
ing
Af
ter
co
n
s
id
er
i
n
g
all
o
th
er
s
t
ag
es,
th
e
r
esear
ch
er
w
it
h
th
e
s
h
ar
ed
ex
p
er
ien
ce
s
o
f
th
e
non
-
m
aj
o
r
s
r
ev
is
ed
o
r
r
ec
o
n
s
id
er
ed
th
e
Sch
o
o
l a
n
d
So
cial
I
s
s
u
es M
o
d
el
f
o
r
T
ea
ch
in
g
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
E
R
E
I
SS
N:
2252
-
8822
Tea
ch
in
g
w
ith
S
o
cio
-
S
cien
tifi
c
I
s
s
u
es in
P
h
ysica
l S
cien
ce
:
T
ea
ch
er a
n
d
S
tu
d
e
n
ts
'
E
xp
erien
ce
s
(
Jo
y
Ta
len
s
)
273
3.
RE
SU
L
T
S
A
ND
AN
AL
Y
SI
S
I
n
d
is
cu
s
s
i
n
g
th
e
r
e
s
u
l
ts
o
f
t
h
i
s
s
t
u
d
y
,
t
h
e
Sc
h
o
o
l
an
d
So
cial
I
s
s
u
e
s
m
o
d
el
b
y
L
e
v
i
n
s
o
n
(
2
0
0
8
)
w
a
s
u
s
ed
b
y
th
e
r
e
s
ea
r
ch
er
t
h
r
o
u
g
h
ax
ial
co
d
in
g
to
a
n
al
y
ze
ex
p
er
ien
ce
s
o
f
t
h
e
teac
h
er
a
n
d
s
t
u
d
en
ts
[
3
]
.
B
ased
o
n
th
e
f
in
d
i
n
g
s
o
f
t
h
is
s
tu
d
y
,
a
m
o
d
el
o
f
lear
n
in
g
ap
p
r
o
ac
h
f
o
r
teac
h
in
g
S
SI
w
a
s
p
r
o
p
o
s
ed
.
3
.
1
.
K
no
w
ledg
e
o
f
Science
w
ill
h
elp
s
t
ud
ent
s
a
s
cit
izens
in
t
h
e
m
a
k
i
ng
t
o
ho
ld
a
nd
ex
press
a
v
iew
o
n
is
s
ue
s
w
hich
ent
er
t
he
a
re
na
o
f
pu
bli
c
deba
t
e
a
nd
perha
p
s
beco
m
e
a
ct
iv
ely
inv
o
lv
ed
i
n so
m
e
a
re
a
s
Mo
s
t st
u
d
en
t
s
w
er
e
ab
le
to
r
ea
d
co
m
p
r
eh
e
n
s
iv
e
l
y
th
e
ar
ticles
.
So
m
e
o
f
th
e
m
s
h
ar
ed
th
at
th
e
y
r
ea
d
th
e
ar
ticles
t
h
r
ee
to
f
i
v
e
ti
m
e
s
to
u
n
d
er
s
ta
n
d
t
h
e
is
s
u
e
.
Oth
er
s
s
h
ar
ed
th
a
t
t
h
e
y
h
ad
to
s
ca
n
,
s
k
i
m
a
n
d
j
o
t
d
o
w
n
i
m
p
o
r
tan
t
p
o
in
ts
i
n
t
h
e
ar
tic
le
s
.
On
e
s
t
u
d
en
t
s
h
ar
ed
th
at
in
d
ee
d
ex
ten
s
i
v
e
r
ea
d
in
g
s
h
o
u
ld
b
e
d
o
n
e
th
at
w
a
s
t
h
e
r
ea
s
o
n
w
h
y
h
e
r
ea
d
th
e
ar
ticle
1
2
tim
e
s
.
Af
ter
r
ea
d
in
g
,
m
a
n
y
s
t
u
d
en
t
s
ex
p
lai
n
ed
th
at
t
h
e
y
an
al
y
z
ed
t
h
e
is
s
u
e
th
r
o
u
g
h
t
h
e
h
elp
o
f
g
u
id
e
q
u
e
s
tio
n
s
g
i
v
en
.
T
h
e
y
d
id
th
is
to
g
ath
er
i
m
p
o
r
tan
t
id
ea
s
th
at
w
i
ll
h
elp
an
s
w
er
t
h
e
q
u
esti
o
n
s
.
On
e
s
t
u
d
en
t
e
m
p
h
a
s
ized
th
at:
“a
n
a
lyzi
n
g
S
S
I
r
eq
u
ir
ed
th
em
to
r
ea
d
b
etw
ee
n
a
n
d
b
ey
o
n
d
th
e
lin
es
th
a
t
d
id
n
o
t
o
n
ly
r
eq
u
ir
e
th
e
m
to
fo
cu
s
o
n
th
e
ma
in
is
s
u
e
o
r
id
ea
b
u
t
ca
r
efu
l
ex
p
lo
r
a
tio
n
o
f
th
e
co
n
te
n
ts
o
f
th
e
a
r
ticles
s
h
o
u
ld
b
e
d
o
n
e
.”
A
n
o
th
er
s
tu
d
e
n
t
ar
g
u
ed
th
at:
“
th
is
a
ctivity
en
ta
iled
u
s
to
s
ea
r
ch
fo
r
mo
r
e
fa
cts
p
a
r
ticu
la
r
ly
o
n
th
e
to
p
ic
B
a
t
a
a
n
N
u
clea
r
P
o
w
er
P
la
n
t
b
e
ca
u
s
e
th
e
a
r
t
icle
w
a
s
n
o
t
en
o
u
g
h
to
p
r
esen
t
p
r
o
s
a
n
d
co
n
s
o
f h
a
r
n
ess
in
g
th
is
n
o
n
-
r
en
ewa
b
le
s
o
u
r
ce
o
f e
n
erg
y.
”
He
f
u
r
th
er
e
m
p
h
as
ized
th
at:
“
I
r
ea
lly
h
a
d
to
lo
o
k
o
n
ea
ch
o
f
th
e
ve
r
y
d
eta
ils
o
f
th
e
is
s
u
e
.
Th
u
s
,
ca
r
efu
l
in
ve
s
tig
a
tio
n
s
h
o
u
ld
b
e
d
o
n
e
b
efo
r
e
o
n
e
ca
n
ma
ke
a
s
ta
n
d
o
n
a
n
is
s
u
e
like
th
is
”.
T
h
ey
al
s
o
s
h
ar
ed
th
at
a
f
ter
a
n
al
y
z
in
g
t
h
e
ar
ticle,
th
e
y
e
v
e
n
co
m
p
ar
ed
th
e
co
n
ten
ts
o
f
t
h
e
ar
ticles
t
h
e
y
g
at
h
er
ed
an
d
th
eir
n
o
tes
in
P
h
y
s
ical
S
cien
ce
.
A
f
ter
d
o
in
g
th
is
,
m
o
s
t
s
t
u
d
en
t
s
co
n
d
u
cted
b
r
ain
s
to
r
m
in
g
ac
ti
v
it
y
w
i
th
t
h
eir
p
ar
tn
er
.
Oth
er
s
tu
d
en
t
s
s
h
ar
ed
th
at:
“
in
th
e
p
r
o
ce
s
s
o
f
b
r
a
in
s
to
r
min
g
,
th
e
y
w
ere
a
b
le
to
d
is
cu
s
s
th
in
g
s
o
n
s
o
u
r
ce
s
o
f
en
erg
y
th
a
t
w
ere
n
o
t
b
ee
n
d
is
cu
s
s
ed
in
th
e
cla
s
s
r
o
o
m
a
n
d
w
il
l
n
o
lo
n
g
er
a
n
s
w
er
th
e
g
u
id
e
q
u
esti
o
n
s
b
efo
r
e
a
r
r
ivin
g
a
t
th
eir
s
ta
n
d
o
n
th
e
SSI
.
”Oth
er
s
s
aid
th
e
y
ev
e
n
e
x
p
er
ien
ce
d
b
r
ain
s
to
r
m
in
g
w
i
t
h
in
th
e
m
s
elv
e
s
.
So
m
e
c
lai
m
e
d
th
at
th
er
e
ar
e
s
t
ill
q
u
esti
o
n
s
i
n
th
eir
m
i
n
d
s
th
at
w
er
e
le
f
t u
n
a
n
s
w
er
ed
p
ar
ticu
l
ar
l
y
o
n
en
er
g
y
co
n
s
u
m
p
tio
n
.
I
n
ter
m
s
o
f
co
n
s
eq
u
e
n
ce
s
,
m
o
s
t
s
t
u
d
en
t
s
s
h
ar
ed
t
h
at:
“a
n
a
l
yzin
g
S
S
I
en
a
b
led
th
em
to
lo
o
k
in
to
th
e
p
r
o
s
a
n
d
co
n
s
o
f
h
a
r
n
ess
in
g
n
u
clea
r
a
n
d
h
yd
r
o
elec
tr
ic
en
erg
y
a
s
w
ell
a
s
fo
s
s
il
fu
els
th
r
o
u
g
h
r
ela
tin
g
is
s
u
es
to
w
h
a
t
th
ey
lea
r
n
ed
in
cla
s
s
a
n
d
th
e
fa
cts
th
a
t
th
ey
s
ea
r
c
h
ed
in
th
e
i
n
tern
et
.
”Sev
er
al
s
tu
d
en
t
s
s
h
ar
ed
th
at
tr
u
l
y
j
u
m
p
i
n
g
in
to
co
n
c
lu
s
io
n
at
o
n
ce
w
it
h
o
u
t
f
ir
s
t
an
a
l
y
zi
n
g
th
e
i
s
s
u
e
w
i
ll
lead
o
n
e
to
n
o
w
h
er
e
s
a
m
e
w
i
t
h
p
r
o
b
lem
s
o
n
e
n
er
g
y
.
I
n
ter
m
s
o
f
m
ea
n
in
g
s
,
th
e
n
o
n
-
m
aj
o
r
s
ex
p
lai
n
ed
th
at
lear
n
i
n
g
SS
I
o
n
s
o
u
r
ce
s
o
f
en
er
g
y
g
av
e
th
e
m
th
e
ch
a
n
ce
to
ex
p
r
ess
th
eir
o
w
n
in
ter
p
r
e
tatio
n
s
o
f
th
e
is
s
u
es
.
On
e
s
t
u
d
en
t
f
u
r
t
h
er
ex
p
lai
n
ed
th
at:
“S
S
I
a
ls
o
en
a
b
led
me
to
w
id
en
my
u
n
d
e
r
s
ta
n
d
in
g
w
h
y
p
eo
p
le
ke
ep
o
n
h
o
ld
in
g
to
w
h
a
t
th
ey
b
eliev
e
in
a
n
d
fig
h
tin
g
fo
r
like
w
h
a
t
h
a
p
p
en
ed
in
th
e
co
n
s
tr
u
ctio
n
o
f
a
h
yd
r
o
elec
tr
ic
p
o
w
er
p
la
n
t
in
Min
d
a
n
a
o
p
eo
p
le
s
a
crif
iced
th
ei
r
lives
to
ex
p
r
e
s
s
th
a
t
th
ey
o
p
p
o
s
ed
th
e
b
u
ild
in
g
o
f
th
a
ts
o
u
r
ce
o
f
en
erg
y
in
fa
vo
r
o
f
th
eir
a
n
ce
s
tr
a
l
la
n
d
a
n
d
cu
ltu
r
a
l
h
erit
a
g
e”.
L
ik
e
w
is
e,
s
o
m
e
s
t
u
d
en
t
s
s
h
ar
ed
t
h
at
th
r
o
u
g
h
S
SI
t
h
e
y
w
er
e
ab
le
to
lear
n
t
h
at
th
er
e
ar
e
m
an
y
d
i
f
f
er
en
tp
lace
s
in
th
e
P
h
ilip
p
in
es
to
o
b
tain
en
er
g
y
.
Oth
er
s
ad
d
ed
th
at
s
o
m
e
o
f
t
h
ese
p
lace
s
ar
e
co
m
m
o
n
l
y
h
ea
r
d
an
d
o
th
er
s
ar
e
m
o
s
t
u
n
li
k
el
y
.
I
n
ad
d
itio
n
to
th
i
s
,
o
n
e
n
o
n
-
m
aj
o
r
q
u
esti
o
n
ed
w
h
y
n
o
t
all
p
eo
p
le
k
n
o
w
ab
o
u
t
w
h
er
e
en
e
r
g
y
i
n
o
u
r
co
u
n
tr
y
co
m
e
s
f
r
o
m
.
Sh
e
cited
t
h
at
“I
a
m
ju
s
t
w
o
n
d
erin
g
w
h
eth
er
w
e
r
ea
lly
h
a
ve
ma
n
y
p
la
ce
s
in
th
e
co
u
n
tr
y
w
h
ere
w
e
ca
n
g
ete
n
erg
y.
I
o
n
ly
h
ea
r
d
a
b
o
u
t
d
a
ms
a
n
d
fa
lls
.
W
h
y
y
u
n
til
n
o
w
n
o
t
a
ll
citiz
en
s
kn
o
w
w
h
ere
w
e
g
et
en
erg
y
?
W
e
ju
s
t
th
o
u
g
h
t
th
a
t
w
e
r
ea
lly
h
a
ve
to
imp
o
r
t
fr
o
m
o
th
er
co
u
n
tr
ies.”
T
o
ex
p
lain
th
is
f
u
r
t
h
er
,
o
n
e
n
o
n
-
m
aj
o
r
s
a
id
th
at:
“
it
is
g
o
o
d
to
k
n
o
w
th
a
t
o
u
r
co
u
n
tr
y
h
a
s
th
ese
a
lter
n
a
tive
s
o
u
r
ce
s
o
f
en
erg
y
a
n
d
fa
milia
r
ity
w
it
h
its
h
is
to
r
y
a
s
w
el
l
a
s
th
eir
a
d
va
n
ta
g
es
a
n
d
d
is
a
d
va
n
ta
g
es
a
r
e
ma
d
e
kn
o
w
n
th
r
o
u
g
h
a
n
a
lyzi
n
g
S
S
I
.
”
A
n
o
th
er
s
t
u
d
e
n
t
s
aid
t
h
at:
“
I
ca
me
to
r
ea
li
z
e
th
a
t
ev
ery
co
n
flict
a
n
d
is
s
u
e
o
u
r
co
u
n
tr
y
is
fa
cin
g
r
o
o
ted
fr
o
m
l
imited
s
o
u
r
ce
s
o
f
en
erg
y.
Th
u
s
,
it
is
b
u
t
p
r
o
p
er
to
u
n
d
ers
ta
n
d
th
a
t we c
a
n
h
a
r
n
ess
a
lter
n
a
tive
s
o
u
r
ce
s
o
f e
n
erg
y
w
h
ich
a
n
a
lyzi
n
g
S
S
I
p
r
o
vid
ed
.”
As
o
b
s
er
v
ed
b
y
t
h
e
teac
h
er
–
r
esear
ch
er
,
n
o
n
–
m
aj
o
r
s
g
ath
er
ed
a
lo
t
o
f
i
n
f
o
r
m
atio
n
to
a
n
al
y
ze
SS
I
.
Du
r
in
g
clas
s
r
o
o
m
d
is
cu
s
s
io
n
,
s
tu
d
en
t
s
ac
tiv
e
l
y
p
ar
ticip
ate
d
b
y
ad
d
in
g
i
n
f
o
r
m
atio
n
to
t
h
e
less
o
n
b
ased
o
n
w
h
at
th
e
y
r
ea
d
a
n
d
r
esear
ch
e
d
o
n
.
A
s
an
ex
a
m
p
le,
s
ev
er
al
s
t
u
d
en
t
s
v
o
lu
n
teer
ed
to
e
x
p
l
ain
h
o
w
to
g
e
n
er
ate
en
er
g
y
f
r
o
m
s
o
lar
ce
ll
s
.
T
h
e
y
ex
p
lai
n
ed
i
n
th
eir
o
w
n
w
o
r
d
s
a
n
d
t
h
r
o
u
g
h
e
x
a
m
p
le
ad
v
a
n
ta
g
es
an
d
d
is
ad
v
an
ta
g
e
s
o
f
s
o
lar
p
o
w
er
.
T
h
ey
w
er
e
ab
le
to
e
n
u
m
er
ate
p
r
o
v
in
ce
s
lik
e
i
n
C
ag
a
y
a
n
d
e
Or
o
in
Min
d
an
ao
,
P
h
i
lip
p
in
es.
I
t
w
a
s
a
ls
o
o
b
s
er
v
ed
th
at
s
t
u
d
en
ts
a
s
k
ed
q
u
esti
o
n
s
o
n
t
h
e
to
p
ic.
O
n
e
o
f
t
h
e
q
u
esti
o
n
s
r
aised
w
a
s
o
n
t
h
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s
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p
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[
1
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No
n
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m
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s
w
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co
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ted
w
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all
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I
t
is
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i
m
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th
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k
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em
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ce
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[
2
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r
ef
lecte
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h
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it
izen
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ci
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j
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s
[
3
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.
T
h
is
i
s
r
elate
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p
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tu
d
y
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-
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tr
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tr
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[
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3
.
2
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I
nd
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id
ua
ls
U
nd
er
s
t
a
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T
he
M
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t
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Which
Science
Der
iv
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T
he
E
v
idence
f
o
r
T
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Cla
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m
s
M
a
de
by
Scient
is
t
s
[
3
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I
n
ter
m
s
o
f
s
tr
ate
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ies,
all
s
tu
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ts
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o
llo
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c
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d
to
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l
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Asi
d
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f
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t
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ar
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ticles;
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p
o
w
er
p
la
n
t
in
Min
d
a
n
a
o
,
B
a
t
a
a
n
N
u
clea
r
P
o
w
er
P
la
n
t
a
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B
ern
h
a
mR
is
e
.
”
A
cc
o
r
d
in
g
to
o
n
e
o
f
t
h
e
s
tu
d
e
n
ts
,
“
i
n
fo
r
ma
tio
n
fo
u
n
d
in
th
e
in
te
r
n
et
h
elp
ed
h
er
to
u
n
d
ers
ta
n
d
w
o
r
d
s
in
th
e
a
r
ticles
th
a
t
a
r
e
d
iffi
cu
lt
to
u
n
d
ers
ta
n
d
.
A
r
ticles
in
th
e
in
tern
et
a
ls
o
p
r
o
vid
e
b
a
ck
g
r
o
u
n
d
in
f
o
r
ma
tio
n
o
n
th
e
to
p
ic
.”
I
t
also
s
u
p
p
lem
e
n
ts
o
u
r
d
is
cu
s
s
io
n
i
n
th
e
clas
s
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o
o
m
s
o
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at
w
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en
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a.
lea
rn
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ro
m
c
l
a
ss
ro
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m
d
isc
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ss
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re
a
d
a
rti
c
les
c
o
m
p
re
h
e
n
siv
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c
o
n
d
u
c
ted
b
ra
in
sto
rm
in
g
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c
ti
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it
y
d.
se
a
rc
h
e
d
f
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r
m
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re
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o
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th
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issu
e
s
lo
o
k
e
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i
n
to
p
r
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d
c
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o
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th
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i
ss
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e
s
e
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p
re
ss
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d
o
n
e
‟s o
w
n
in
terp
re
tati
o
n
s o
f
th
e
issu
e
s
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
E
R
E
I
SS
N:
2252
-
8822
Tea
ch
in
g
w
ith
S
o
cio
-
S
cien
tifi
c
I
s
s
u
es in
P
h
ysica
l S
cien
ce
:
T
ea
ch
er a
n
d
S
tu
d
e
n
ts
'
E
xp
erien
ce
s
(
Jo
y
Ta
len
s
)
275
less
o
n
s
i
n
clas
s
,
t
h
e
ar
ticles
a
n
d
th
e
r
e
s
ea
r
ch
es
g
at
h
er
ed
f
r
o
m
t
h
e
i
n
ter
n
et
ar
e
co
m
b
in
ed
,
c
o
n
clu
s
io
n
s
ca
n
b
e
ar
r
iv
ed
at.
T
h
u
s
,
a
d
ec
is
io
n
ca
n
b
e
m
ad
e
r
e
g
ar
d
in
g
o
n
e‟
s
s
tan
d
o
n
t
h
e
i
s
s
u
es.”
L
ikewi
s
e,
o
n
e
s
tu
d
en
t a
d
d
ed
th
a
t
fr
o
m
th
e
g
a
th
ered
a
r
ticles
in
t
h
e
in
tern
et,
s
h
e
w
a
s
a
b
le
to
c
a
r
efu
lly
d
elin
ea
te
fa
cts
o
n
th
e
a
r
ticles
w
ith
s
o
cio
-
s
cien
tifi
c
is
s
u
es.
”
Mo
r
eo
v
er
,
an
o
th
er
s
t
u
d
en
t
ex
p
lai
n
ed
th
at:
“
a
fte
r
r
ea
d
in
g
th
e
a
r
ticles
s
ev
era
l
ti
mes
p
a
r
ticu
la
r
ly
a
n
a
r
ticle
o
n
B
ern
h
a
m
R
is
e,
I
w
a
s
a
b
le
to
b
r
o
w
s
e
o
th
er
ex
a
mp
les
o
r
s
imila
r
s
ce
n
a
r
io
s
a
ll
o
ve
r
th
e
w
o
r
ld
a
n
d
co
mp
a
r
e
th
eir
s
imila
r
i
ties
a
n
d
d
iffer
en
ce
s
w
h
ich
co
u
ld
h
elp
me
to
co
me
u
p
w
ith
clea
r
u
n
d
ers
ta
n
d
in
g
o
f
th
e
to
p
ic
a
n
d
ma
ke
a
s
ta
n
d
o
n
th
e
is
s
u
e
.
”
T
h
er
e
w
er
e
g
r
o
u
p
s
o
f
s
t
u
d
en
t
s
w
h
o
clai
m
ed
t
h
at
th
e
y
r
ea
d
m
a
n
y
b
o
o
k
s
r
elate
d
to
th
e
ar
ticle.
Af
ter
r
ea
d
in
g
,
t
h
e
y
ev
al
u
ated
th
e
p
r
o
s
an
d
co
n
s
o
f
ev
er
y
d
ec
is
io
n
m
ad
e
b
y
p
er
s
o
n
alitie
s
i
n
v
o
lv
ed
in
th
e
is
s
u
e
s
.
L
i
k
e
w
is
e,
t
h
e
y
clas
s
i
f
ied
i
m
p
o
r
tan
t
s
tate
m
en
ts
o
f
ea
c
h
s
id
e
w
h
et
h
er
o
p
in
io
n
o
r
f
ac
t.I
n
d
ee
d
,
th
e
n
o
n
-
m
aj
o
r
s
n
ev
er
s
to
p
p
ed
in
f
i
n
d
in
g
w
a
y
s
to
a
n
al
y
ze
SS
I
.
T
h
e
y
co
n
d
u
cted
b
ig
g
r
o
u
p
d
is
cu
s
s
io
n
s
d
u
r
in
g
th
eir
f
r
ee
ti
m
e.
T
h
e
y
s
h
ar
ed
ea
ch
o
th
er
‟
s
id
ea
s
an
d
o
p
in
io
n
s
an
d
w
r
ite
th
e
m
d
o
w
n
.
T
h
r
o
u
g
h
t
h
is
,
t
h
e
y
p
r
o
v
ed
th
at
t
h
e
y
u
n
d
er
s
tan
d
t
h
e
s
ce
n
ar
io
an
d
all
t
h
e
d
etails
f
r
o
m
t
h
e
ar
ticles,
class
r
o
o
m
d
is
c
u
s
s
io
n
a
n
d
r
ese
ar
ch
es
f
r
o
m
I
n
ter
n
et
a
n
d
b
o
o
k
s
.
Oth
er
s
d
id
s
m
al
l
g
r
o
u
p
d
is
c
u
s
s
io
n
w
h
er
e
th
e
y
d
r
e
w
d
ia
g
r
a
m
co
n
s
is
t
s
o
f
t
wo
co
lu
m
n
s
f
o
r
t
h
e
p
r
o
s
a
n
d
c
o
n
s
to
d
if
f
er
en
t
iate
o
n
e
f
r
o
m
an
o
t
h
er
.
T
h
e
y
a
ls
o
s
h
ar
ed
th
at
th
r
o
u
g
h
th
e
d
iag
r
a
m
,
th
e
y
w
er
e
ab
le
to
co
m
p
ar
e
ev
id
en
ce
s
to
p
r
o
v
e
th
eir
ar
g
u
m
en
ts
.
T
h
er
e
w
er
e
also
s
m
all
g
r
o
u
p
s
th
a
t
s
h
ar
ed
all
th
e
in
f
o
r
m
at
io
n
th
e
y
g
a
th
e
r
ed
.
T
h
ey
b
elie
v
ed
th
at
t
h
r
o
u
g
h
s
h
ar
i
n
g
,
th
e
y
ca
n
u
n
d
er
s
ta
n
d
t
h
e
i
s
s
u
es
b
etter
.
An
o
th
er
g
r
o
u
p
s
h
ar
ed
t
h
at
i
n
t
h
eir
s
m
a
ll
g
r
o
u
p
d
is
c
u
s
s
io
n
th
e
y
tal
k
ed
ab
o
u
t
ea
c
h
o
n
e‟
s
r
ea
ctio
n
s
to
t
h
e
ar
ticle
s
th
at
lead
to
ar
g
u
m
e
n
ts
o
n
p
o
s
s
ib
le
ca
u
s
es
a
n
d
e
f
f
ec
ts
o
f
h
ar
n
es
s
in
g
al
ter
n
ati
v
e
s
o
u
r
ce
s
o
f
e
n
er
g
y
.
I
n
ter
m
s
o
f
p
ar
ticip
atio
n
,
th
e
n
o
n
-
m
aj
o
r
s
ex
p
lain
ed
t
h
at
in
o
r
d
er
f
o
r
th
e
m
to
u
n
d
er
s
tan
d
S
SI,
“w
e
d
is
cu
s
s
ed
w
i
th
o
u
r
cla
s
s
ma
tes
th
e
co
n
te
n
ts
.
A
fter
w
e
co
n
d
u
cted
o
u
r
o
w
n
r
ea
d
in
g
s
s
ev
era
ltimes
,
w
e
a
s
ke
d
o
n
e
a
n
o
th
er
a
b
o
u
t
o
u
r
o
p
in
io
n
s
a
n
d
r
ea
ctio
n
s
o
n
t
h
e
to
p
ic
.
”M
o
s
t
s
tu
d
en
ts
s
h
ar
ed
th
a
t
th
r
o
u
g
h
b
r
a
in
s
to
r
min
g
,
th
ey
w
ere
a
b
le
to
a
n
s
w
er
th
e
g
u
id
e
q
u
esti
o
n
s
.
Ho
w
e
v
er
,
th
er
e
w
er
e
s
o
m
e
g
r
o
u
p
s
o
f
n
o
n
-
m
aj
o
r
s
w
h
o
clai
m
ed
th
a
t wh
en
w
e
fin
a
liz
ed
o
u
r
a
n
s
w
ers
a
n
d
a
lr
ea
d
y
i
n
th
e
p
r
o
ce
s
s
o
f
en
co
d
in
g
th
em,
w
e
ev
en
ch
a
n
g
ed
o
u
r
a
n
s
w
ers
a
ll
o
f
a
s
u
d
d
en
b
ec
a
u
s
e
eith
er
o
n
e
o
f
u
s
o
r
b
o
th
o
f
u
s
w
ill
s
till
a
r
g
u
e
a
n
d
p
r
o
vid
e
ev
id
en
ce
o
r
p
r
o
o
f
th
a
t
th
ere
i
s
s
till
a
p
o
s
s
ib
le
a
n
s
w
er
to
th
e
q
u
esti
o
n
”.
T
h
ey
ad
d
ed
th
at
in
th
e
p
r
o
ce
ss
,
th
e
y
b
ec
am
e
v
er
y
cr
itica
l th
i
n
k
er
s
.
I
n
ter
m
s
o
f
co
n
d
itio
n
,
n
o
n
-
m
aj
o
r
s
o
b
s
er
v
ed
th
at
lear
n
i
n
g
s
cien
ce
t
h
r
o
u
g
h
SS
I
is
s
i
m
ilar
to
a
ca
s
e
d
ig
est
th
at
is
p
ar
t
o
f
t
h
e
r
eq
u
ir
e
m
en
ts
o
f
co
u
r
s
es
in
B
ac
h
e
lo
r
o
f
Scie
n
ce
in
L
eg
al
Ma
n
a
g
e
m
e
n
t.
T
h
e
y
al
s
o
n
o
ticed
th
at
th
er
e
w
er
e
s
o
m
e
g
u
id
e
q
u
esti
o
n
s
t
h
at
w
er
e
d
i
f
f
icu
lt
to
co
m
p
r
e
h
en
d
r
eq
u
ir
i
n
g
th
e
m
to
ex
er
t
e
x
tr
a
ef
f
o
r
t
to
u
n
d
er
s
ta
n
d
.
Ho
w
e
v
e
r
,
s
o
m
e
s
t
u
d
en
t
s
ar
g
u
ed
t
h
at
“in
s
tea
d
o
f
lo
o
ki
n
g
a
t
lea
r
n
i
n
g
th
r
o
u
g
h
S
S
I
a
s
a
d
iffi
cu
lt
ta
s
k,
th
ey
ju
s
t
fo
cu
s
o
n
g
a
th
erin
g
fa
cts
a
n
d
o
p
in
io
n
s
to
b
ette
r
u
n
d
ers
ta
n
d
th
e
is
s
u
es
a
n
d
a
n
s
w
er
th
e
q
u
esti
o
n
s
b
ec
a
u
s
e
w
h
ywa
s
te
t
ime
fo
r
th
in
kin
g
th
a
t
it
is
d
iffi
cu
lt
to
a
cc
o
mp
lis
h
w
h
ile
in
r
ea
l
life
d
ea
lin
g
w
ith
th
ese
is
s
u
es o
n
s
o
u
r
ce
s
o
f e
n
erg
y
is
r
ea
lly
ve
r
y
cru
cia
l”.
I
n
ter
m
s
o
f
s
tate,
s
e
v
er
al
s
t
u
d
e
n
ts
cla
i
m
ed
t
h
at:
“
tea
ch
in
g
th
r
o
u
g
h
S
S
I
en
a
b
led
u
s
to
r
ea
d
a
r
ticles
th
a
t
ta
ck
led
is
s
u
es
n
o
t
kn
o
w
n
to
m
a
n
y
b
efo
r
e
p
a
r
ticu
la
r
ly
o
n
B
ern
h
a
m
R
is
ewh
ich
w
h
en
b
ec
o
me
o
fficia
lly
p
a
r
t
o
f
th
eP
h
ilip
p
in
e
Ter
r
ito
r
y
w
il
l
b
e
a
n
o
th
er
p
o
s
s
ib
leso
u
r
ce
o
f
a
lter
n
a
tive
en
erg
y.
”
T
h
ey
s
aid
th
at
i
n
s
o
m
e
w
a
y
SS
I
m
ad
e
th
e
m
g
r
ate
f
u
l
a
n
d
h
o
p
ef
u
l
t
h
at
if
th
er
e
ar
e
p
o
s
s
ib
l
e
alter
n
ati
v
e
s
o
u
r
ce
s
o
f
e
n
er
g
y
s
o
m
e
h
o
w
w
e
ca
n
p
o
s
s
ib
l
y
f
in
d
a
s
o
l
u
tio
n
to
h
is
p
r
o
b
lem
.
L
ik
e
w
i
s
e,
m
o
s
t
n
o
n
–
m
aj
o
r
s
s
h
ar
ed
th
at
S
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es c
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er
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d
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al
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eg
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w
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g
if
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ar
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er
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ain
s
t th
e
m
a
n
al
y
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ir
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t t
h
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s
ta
n
d
.
In
ter
m
s
o
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co
n
s
eq
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e
n
ce
s
,
t
h
e
n
o
n
–
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r
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s
h
ar
ed
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n
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n
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er
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d
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t
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d
en
t
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s
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ld
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n
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ir
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t
th
e
ar
tic
les
–
w
h
at
ar
e
th
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y
all
ab
o
u
t.
So
m
e
s
tu
d
e
n
ts
e
lab
o
r
ated
th
at
o
n
e
s
h
o
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ld
f
ir
s
t
r
ea
d
th
e
ar
ticles
ca
r
ef
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ll
y
an
d
p
u
t
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o
u
r
h
ea
r
t
in
to
it.M
o
s
t
o
f
th
e
m
o
b
s
er
v
ed
th
at
th
e
s
e
is
s
u
es
ar
e
ev
er
y
o
n
e
‟
s
co
n
ce
r
n
b
ec
au
s
e
th
e
to
p
ic
is
o
n
en
er
g
y
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n
d
ev
er
y
o
n
e
is
u
s
in
g
it.
An
o
th
e
r
s
t
u
d
en
t
ad
d
ed
th
at
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n
a
lyzi
n
g
S
S
I
ma
d
e
me
feel
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h
a
t
I
s
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o
u
ld
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ea
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s
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d
y
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lter
n
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tive
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r
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s
o
f
en
erg
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in
o
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n
tr
ya
n
d
b
e
vig
ila
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t
w
ith
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h
a
t
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g
o
in
g
o
n
in
o
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r
co
u
n
tr
y
p
erta
in
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g
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ic
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ma
tter
w
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t
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ig
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r
s
m
a
ll
th
eir
d
is
co
ve
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y
o
r
is
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u
e
is
”.
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eo
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e
s
h
ar
ed
th
at:
it
m
ad
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m
y
i
m
ag
in
atio
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w
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r
k
ed
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s
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m
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“w
h
a
t if
s
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i
n
m
y
m
i
n
d
li
k
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“
w
h
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t if
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e
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o
ve
r
n
men
t wi
ll
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t
p
r
io
r
itiz
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b
lems
o
r
co
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n
s
o
n
en
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s
o
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r
ce
s
;
w
h
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t
if
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n
o
th
erco
u
n
tr
y
w
ill
cla
im
B
er
n
h
a
m
R
is
e;
w
h
a
t
i
f
B
a
ta
a
n
N
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clea
r
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o
w
er
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la
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t
w
il
l
b
e
a
llo
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era
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ased
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e
e
x
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lan
at
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ab
o
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e,
m
a
n
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ts
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ter
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m
o
s
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m
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r
s
clai
m
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s
i
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g
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ab
led
t
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e
m
t
o
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m
e
cr
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r
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.
T
h
is
is
s
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as
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d
en
t
s
tated
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h
elp
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h
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a
lo
t
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n
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er
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ticle
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ical
Scie
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Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:2
2
5
2
-
8822
I
J
E
R
E
Vo
l.
5
,
No
.
4
,
Dec
em
b
er
2
0
1
6
:
271
-
2
8
3
276
s
tated
th
at
S
SI
en
ab
led
h
er
to
an
s
w
er
q
u
es
tio
n
s
n
o
t
o
n
l
y
b
ased
o
n
b
o
o
k
s
o
r
lectu
r
eb
u
t
s
h
o
u
ld
b
e
b
ased
o
n
ev
id
en
ce
s
.
B
ased
o
n
th
e
e
x
p
er
ien
ce
s
o
f
th
e
teac
h
er
–
r
esear
ch
er
,
n
o
n
–
m
aj
o
r
s
f
o
llo
w
ed
th
e
s
tep
s
in
s
cien
ti
f
ic
m
et
h
o
d
w
h
ic
h
t
h
e
y
s
t
u
d
ied
b
ef
o
r
e.
T
h
ey
w
er
e
ab
le
to
id
en
ti
f
y
th
e
p
r
o
b
le
m
i
n
ea
c
h
o
f
th
e
ar
ticle
s
g
iv
e
n
.
T
h
is
w
as
e
v
id
en
t
d
u
r
i
n
g
cla
s
s
r
o
o
m
d
is
cu
s
s
io
n
w
h
er
ei
n
s
t
u
d
en
ts
p
ar
ticip
ated
ac
tiv
el
y
b
y
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iv
i
n
g
t
h
e
i
d
en
ti
f
ied
p
r
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b
lem
as
e
x
a
m
p
les.
T
h
e
y
e
v
en
e
x
p
lai
n
ed
d
etails
o
n
w
h
y
t
h
ese
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r
o
b
le
m
s
co
n
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r
n
i
n
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en
er
g
y
o
cc
u
r
r
ed
o
r
h
ap
p
en
ed
.
So
m
e
n
o
n
–
m
aj
o
r
s
also
m
en
tio
n
ed
s
o
u
r
ce
s
o
r
r
ef
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e
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es
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h
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y
s
h
ar
ed
.
T
h
r
o
u
g
h
t
h
is
,
t
h
e
y
w
er
e
ab
le
to
r
ef
lect
o
n
th
e
is
s
u
e
s
.
Fig
u
r
e
2
s
h
o
w
s
th
at
teac
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n
g
SS
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in
a
P
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Sc
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ce
cla
s
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en
ab
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ts
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ap
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l
y
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at
th
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y
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in
f
o
llo
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in
g
s
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n
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t
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a
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e
m
e
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b
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e
y
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r
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s
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tli
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n
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te
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n
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r
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r
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x
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e
f
f
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b
y
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h
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o
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m
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r
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a
n
al
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is
s
u
es
w
h
ic
h
w
as
s
i
m
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lar
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n
ti
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ts
e
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ce
d
w
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d
is
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v
er
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n
v
e
n
t
o
r
p
r
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v
e
th
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clai
m
s
o
r
h
y
p
o
t
h
esi
s
.
I
t
is
also
w
o
r
t
h
y
t
o
co
n
s
id
er
th
at
n
o
n
-
m
aj
o
r
s
ar
e
n
o
t
ex
p
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ted
to
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ec
o
m
e
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ci
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ts
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n
th
e
f
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r
e
b
u
t
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y
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e
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p
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e
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y
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h
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g
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th
e
s
tep
s
o
r
p
r
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ce
s
s
in
v
o
l
v
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in
s
cie
n
ti
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ic
m
eth
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d
.
T
h
r
o
u
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h
teac
h
in
g
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SI
to
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n
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er
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n
ce
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ased
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m
a
g
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tio
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o
n
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a
t
th
e
y
lear
n
ed
.
T
h
u
s
,
t
h
e
y
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ec
a
m
e
k
n
o
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g
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b
le
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elt
t
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e
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ter
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le
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o
ex
er
t
ef
f
o
r
t
to
lo
o
k
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r
alter
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ati
v
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r
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o
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er
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p
r
ess
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p
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at
s
o
m
ed
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y
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v
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s
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o
f
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g
y
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e
d
is
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v
er
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d
f
elt
as
s
u
r
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n
ce
t
h
at
th
e
g
o
v
er
n
m
en
t
w
i
ll n
o
lo
n
g
er
d
ep
en
d
o
n
f
o
s
s
il
f
u
e
l.
Han
le
y
,
et
al
(
2
0
0
7
)
s
u
p
p
o
r
t
ed
th
e
ab
o
v
e
f
in
d
i
n
g
s
th
at
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SI
en
co
u
r
ag
e
s
a
f
o
cu
s
o
n
“
i
d
ea
s
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ab
o
u
t
-
s
cien
ce
”
(
th
e
p
r
o
ce
s
s
e
s
a
n
d
p
r
ac
tices
o
f
s
cien
ce
)
a
n
d
co
n
s
id
er
atio
n
o
f
s
cie
n
ti
f
ic
e
v
id
e
n
ce
a
n
d
v
al
u
e
s
[
2
]
.
I
n
th
e
s
a
m
e
w
a
y
,
th
e
n
o
n
–
m
aj
o
r
s
as
p
ar
ticip
an
ts
in
th
i
s
s
tu
d
y
w
er
e
ab
le
to
id
en
tify
p
r
o
b
lem
s
in
d
if
f
er
en
t
ar
ticles
o
r
is
s
u
e
s
co
n
ce
r
n
in
g
s
o
u
r
ce
s
o
f
e
n
er
g
y
t
h
at
af
f
ec
t
m
e
m
b
er
s
o
f
th
e
s
o
ciet
y
t
h
r
o
u
g
h
th
e
u
s
e
o
f
s
tep
s
i
n
s
cien
t
if
ic
m
et
h
o
d
.
T
h
ey
w
er
e
ab
le
to
ex
p
lain
w
h
y
p
r
o
b
lem
s
o
cc
u
r
r
ed
s
i
m
ilar
to
th
e
w
a
y
s
cien
t
is
t
s
d
o
th
e
m
.
T
h
is
is
co
n
f
ir
m
ed
b
y
S
u
n
ar
an
d
Gib
an
(
2
0
1
1
)
w
h
o
ex
p
lain
ed
th
at
b
ein
g
citize
n
s
o
f
t
h
e
n
ea
r
f
u
t
u
r
e,
s
tu
d
en
t
s
w
il
l
m
ak
e
d
ec
i
s
io
n
s
r
eq
u
ir
in
g
an
u
n
d
er
s
ta
n
d
in
g
o
f
th
e
in
ter
ac
tio
n
o
f
s
cie
n
ce
an
d
tec
h
n
o
lo
g
y
a
n
d
it
s
i
n
ter
f
ac
e
w
it
h
s
o
ciet
y
[
4
]
.
L
i
k
e
w
i
s
e,
P
h
y
s
ical
Scie
n
ce
s
ee
k
s
to
d
ev
e
lo
p
s
tu
d
en
t
s
i
n
to
w
ell
-
r
o
u
n
d
ed
p
r
o
d
u
ctiv
e
m
e
m
b
er
s
o
f
s
o
ciet
y
,
b
r
o
ad
en
in
g
t
h
eir
p
er
s
p
ec
tiv
es
b
y
ex
p
o
s
i
n
g
th
e
m
to
n
e
w
id
ea
s
an
d
a
d
iv
er
s
it
y
o
f
w
o
r
ld
v
ie
w
s
w
h
ile
g
iv
in
g
t
h
e
m
t
h
e
to
o
ls
to
en
g
a
g
e
th
e
m
[
1
5
]
.
3
.
3
.
Sub
s
ec
t
io
n
A
pp
re
cia
t
e
t
he
s
t
re
ng
t
hs
a
nd
li
m
it
s
o
f
s
cient
if
ic
ev
idenc
e
[
3
]
I
n
ter
m
s
o
f
s
tate,
m
o
s
t
n
o
n
-
m
aj
o
r
s
ag
r
ee
d
th
at:“
a
n
a
lyzi
n
g
S
S
I
a
lth
o
u
g
h
d
iffi
cu
lt
a
t
fir
s
ten
a
b
led
u
s
to
u
n
d
ers
ta
n
d
s
o
u
r
ce
s
o
f
en
erg
yp
a
r
ticu
la
r
ly
in
th
e
P
h
ilip
p
i
n
es
b
etter
b
ec
a
u
s
eth
ese
is
s
u
es
a
r
e
ev
eryb
o
d
y’
s
co
n
ce
r
n
a
s
ev
eryo
n
e
co
n
s
u
mes
en
erg
y”.
T
h
u
s
,
t
h
er
e
w
e
r
e
s
ev
er
al
n
o
n
-
m
aj
o
r
s
w
h
o
clai
m
ed
t
h
at
th
e
y
ap
p
r
ec
iated
th
e
u
s
e
o
f
S
SI
in
th
e
cla
s
s
r
o
o
m
.
O
n
e
s
t
u
d
en
t
wh
o
s
aid
t
h
at
i
n
S
SI,
r
ea
l
lif
e
is
s
u
e
s
o
r
h
ap
p
en
i
n
g
s
th
at
a
f
f
ec
t
ev
er
y
o
n
e
i
n
t
h
e
s
o
ciet
y
w
h
eth
er
r
ic
h
o
r
p
o
o
r
t
h
at
o
n
l
y
p
r
in
c
ip
les
a
n
d
co
n
c
ep
ts
in
s
cie
n
ce
ca
n
ex
p
lain
ex
p
lai
n
th
i
s
.
Se
v
er
al
s
t
u
d
en
t
s
ad
d
ed
th
at
f
o
r
th
e
m
S
SI
is
v
er
y
e
f
f
ec
ti
v
e
f
o
r
n
o
n
-
m
aj
o
r
s
to
u
n
d
er
s
ta
n
d
less
o
n
s
i
n
P
h
y
s
ical
Sc
ien
ce
b
ec
au
s
e
d
etai
ls
a
n
d
n
ee
d
ed
in
f
o
r
m
at
io
n
to
u
n
d
er
s
tan
d
th
e
is
s
u
e
b
ei
n
g
a
n
al
y
ze
d
.
On
e
s
tu
d
e
n
t
ad
d
ed
th
a
t
S
SI
o
p
en
ed
h
er
e
y
es
o
n
i
s
s
u
es
b
ei
n
g
f
ac
ed
b
y
o
u
r
co
u
n
tr
y
w
h
ic
h
n
o
t
e
v
er
y
o
n
e
ar
e
a
w
ar
e
o
f
alt
h
o
u
g
h
th
e
s
e
is
s
u
e
s
af
f
ec
t e
v
er
y
o
n
e.
I
n
ter
m
s
o
f
p
ar
ticip
atio
n
,
n
o
n
-
m
aj
o
r
s
r
ea
lized
th
at
i
n
o
r
d
er
to
ap
p
r
ec
iate
SS
I
in
t
h
e
class
r
o
o
m
,
b
r
ain
s
to
r
m
i
n
g
ac
ti
v
it
y
s
h
o
u
ld
b
e
d
o
n
e
am
o
n
g
s
t
u
d
en
t
s
.
On
e
n
o
n
-
m
aj
o
r
s
h
ar
ed
th
at
d
is
c
u
s
s
in
g
th
e
co
n
ten
ts
o
f
th
e
ar
ticles
w
it
h
h
er
class
m
at
es
ca
n
h
elp
t
h
e
m
u
n
d
er
s
tan
d
b
etter
th
e
is
s
u
e.
An
o
th
er
g
r
o
u
p
o
f
n
o
n
-
m
aj
o
r
s
clai
m
ed
t
h
at:
“
it
is
b
ette
r
to
s
h
a
r
e
id
ea
s
o
r
o
p
in
io
n
s
w
ith
g
r
o
u
p
ma
tes
a
s
w
ell
a
s
r
ea
ctio
n
s
to
th
e
to
p
ics
.
”
An
o
th
er
s
tu
d
e
n
t
ad
d
ed
th
at
t
h
r
o
u
g
h
s
h
ar
i
n
g
s
h
e
g
a
in
ed
m
o
r
e
i
n
f
o
r
m
atio
n
i
n
t
h
e
to
p
ic
th
at
s
h
e
h
ad
n
o
t
en
co
u
n
ter
ed
w
h
ile
co
n
d
u
cti
n
g
r
esear
ch
.
I
n
ter
m
s
o
f
co
n
s
eq
u
en
ce
s
,
it
was f
o
u
n
d
t
h
at
a
lth
o
u
g
h
m
o
s
t
n
o
n
-
m
aj
o
r
s
cited
th
at:
“
a
n
a
lyzi
n
g
S
S
I
w
a
s
q
u
ite
h
a
r
d
t
o
d
o
o
r
a
cc
o
mp
lis
h
a
n
d
w
e
r
ea
liz
ed
th
a
t
in
th
e
p
r
o
ce
s
s
ma
n
y
p
eo
p
le
a
r
e
tr
yin
g
a
ll
p
o
s
s
ib
le
mea
n
s
to
d
is
co
ve
r
a
lter
n
a
tiveso
u
r
ce
s
o
f
en
erg
y
in
th
e
P
h
ilip
p
in
es
.
”
Ma
n
y
ag
r
ee
d
also
t
h
at
t
h
e
y
a
r
e
tr
u
l
y
g
r
ate
f
u
l
to
th
ese
p
eo
p
le
f
o
r
th
e
y
n
e
v
er
s
to
p
s
ea
r
ch
in
g
f
o
r
a
lter
n
a
t
iv
e
s
o
u
r
ce
s
o
f
en
er
g
y
f
o
r
p
r
esen
t
an
d
f
u
t
u
r
e
co
n
s
u
m
p
tio
n
.
I
n
ter
m
s
o
f
m
ea
n
in
g
,
m
an
y
n
o
n
-
m
aj
o
r
s
s
h
ar
ed
th
at
S
SI
i
n
clas
s
g
a
v
e
t
h
e
m
co
n
cr
ete
i
n
f
o
r
m
atio
n
ab
o
u
t
is
s
u
es
o
n
s
o
u
r
ce
s
o
f
e
n
er
g
y
in
t
h
e
P
h
ilip
p
i
n
es
t
h
at
tack
le
all
t
h
eir
ad
v
an
tag
e
s
an
d
d
is
ad
v
an
tag
e
s
.
I
n
ad
d
itio
n
,
m
an
y
o
f
t
h
e
m
b
e
liev
ed
th
at
t
h
e
y
w
er
e
i
n
f
o
r
m
e
d
o
n
w
h
at
alter
n
ati
v
e
s
o
u
r
ce
s
o
f
en
er
g
y
ca
n
b
e
f
o
u
n
d
in
o
u
r
co
u
n
tr
y
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
E
R
E
I
SS
N:
2252
-
8822
Tea
ch
in
g
w
ith
S
o
cio
-
S
cien
tifi
c
I
s
s
u
es in
P
h
ysica
l S
cien
ce
:
T
ea
ch
er a
n
d
S
tu
d
e
n
ts
'
E
xp
erien
ce
s
(
Jo
y
Ta
len
s
)
277
I
t
h
ad
b
ee
n
o
b
s
er
v
ed
th
at
tea
ch
in
g
t
h
r
o
u
g
h
SS
I
w
as
n
o
t
ea
s
y
o
n
th
e
p
ar
t
o
f
th
e
teac
h
er
an
d
o
f
th
e
n
o
n
-
m
aj
o
r
s
.
On
th
e
p
ar
t
o
f
th
e
teac
h
er
,
cr
iter
ia
s
h
o
u
ld
b
e
m
et
to
m
ak
e
s
u
r
e
th
at
th
e
ar
ti
cles
o
r
is
s
u
es
to
b
e
u
s
ed
i
n
cla
s
s
ar
e
w
o
r
t
h
a
n
al
y
z
in
g
.
I
t
m
ea
n
s
t
h
at
t
h
e
i
s
s
u
es
s
h
o
u
ld
b
e
co
n
s
id
er
ed
as
s
u
b
j
ec
t
f
o
r
d
eb
ate
as
t
h
i
s
af
f
ec
t
ev
er
y
m
e
m
b
er
o
f
t
h
e
s
o
ciet
y
an
d
th
e
s
o
lu
tio
n
f
o
r
th
i
s
ca
n
b
e
s
o
lv
ed
o
r
ex
p
lain
ed
its
o
cc
u
r
r
en
ce
th
r
o
u
g
h
u
n
d
er
s
ta
n
d
in
g
s
cie
n
ce
co
n
ce
p
ts
o
r
p
r
in
cip
les.
On
th
e
o
th
er
h
an
d
,
s
t
u
d
en
t
s
f
o
u
n
d
t
h
a
t
th
is
s
tr
ateg
y
w
as
d
if
f
ic
u
lt
a
s
th
e
y
w
er
e
r
eq
u
ir
ed
to
s
p
en
d
m
o
r
e
ti
m
e
to
r
ea
d
,
r
esear
ch
an
d
a
n
al
y
ze
t
h
e
i
s
s
u
e
s
.
Ho
w
e
v
er
,
all
th
e
ti
m
e
th
e
y
s
p
en
t
w
er
e
w
o
r
t
h
it
b
ec
au
s
e
th
e
teac
h
er
-
r
e
s
ea
r
ch
er
n
o
ticed
th
at
d
u
r
in
g
clas
s
r
o
o
m
d
is
c
u
s
s
io
n
t
h
e
y
w
er
e
ab
le
to
g
i
v
e
e
x
a
m
p
les
a
n
d
p
o
in
t
o
u
t
p
lace
s
i
n
t
h
e
co
u
n
t
r
y
w
h
er
e
a
p
ar
ticu
lar
en
er
g
y
s
o
u
r
ce
is
f
o
u
n
d
.
As
a
r
esu
lt
th
e
n
o
n
–
m
aj
o
r
s
w
er
e
ab
le
to
u
n
d
er
s
ta
n
d
t
h
e
i
s
s
u
es
an
d
ap
p
r
ec
iate
th
e
u
s
e
o
f
S
SI
in
a
s
cie
n
ce
clas
s
.
T
h
u
s
,
th
e
y
w
er
e
ab
le
to
s
ee
an
d
ap
p
r
ec
iate
th
e
less
o
n
as
th
i
s
ca
n
b
e
ap
p
lied
in
d
aily
li
f
e.
L
i
k
e
w
is
e,
n
o
n
-
m
aj
o
r
s
w
er
e
g
u
id
ed
o
n
w
h
ich
s
o
u
r
ce
o
f
en
er
g
y
is
f
itted
to
b
e
h
ar
n
e
s
s
in
t
h
e
P
h
ilip
p
in
e
s
.
Fig
u
r
e
2
.
Su
m
m
ar
y
o
f
a
x
ial
co
d
in
g
f
o
r
ap
p
ly
i
n
g
s
cie
n
ti
f
ic
m
eth
o
d
in
s
o
l
v
in
g
t
h
e
is
s
u
e
s
Fig
u
r
e
3
s
h
o
w
s
th
at
a
n
al
y
z
in
g
SS
I
q
u
ite
h
ar
d
to
ac
co
m
p
lis
h
an
d
d
if
f
ic
u
lt
to
d
o
at
f
ir
s
t.
Ho
w
e
v
er
,
th
is
en
ab
led
n
o
n
–
m
aj
o
r
s
to
g
iv
e
co
n
cr
ete
ex
a
m
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u
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t:
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Fig
u
r
e
5
.
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m
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l c
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P
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Scie
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h
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g
h
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m
p
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.
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h
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m
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h
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g
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n
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id
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es
to
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o
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t
h
e
n
o
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–
m
aj
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e
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le
to
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p
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ie
w
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n
d
o
p
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io
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as
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e
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t
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s
o
u
n
d
d
ec
is
io
n
a
n
d
j
u
d
g
m
e
n
t.
As
w
h
at
h
ad
b
ee
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o
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er
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ed
a
m
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n
g
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d
e
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ts
,
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h
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er
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le
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ar
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io
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ch
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eth
e
r
r
en
e
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le
o
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o
n
–
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en
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w
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le.
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h
is
w
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ev
id
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t
w
h
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ts
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ed
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r
ce
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f
e
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er
g
y
is
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est
s
o
u
r
ce
to
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ar
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e
s
s
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n
d
th
e
y
d
id
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y
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i
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e
p
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s
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d
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n
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o
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ch
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.
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h
ey
al
s
o
th
o
u
g
h
t
o
f
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o
s
s
ib
ilit
ies
an
d
ch
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llen
g
es
th
at
m
a
y
b
e
en
co
u
n
ter
ed
if
p
eo
p
le
w
i
ll
s
till
co
n
t
in
u
e
r
el
y
i
n
g
o
n
n
o
n
-
r
e
n
e
w
a
b
le
s
o
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r
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li
k
e
f
o
s
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il
f
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e
ls
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T
h
e
y
w
er
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al
s
o
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u
r
io
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s
o
n
th
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o
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ilit
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o
f
o
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ag
ai
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t
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B
ataa
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clea
r
P
o
w
er
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lan
t.H
o
w
e
v
er
,
m
a
n
y
n
o
n
–
m
aj
o
r
s
ex
p
r
ess
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t
h
eir
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w
s
t
h
at
th
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p
lan
t
m
a
y
o
n
l
y
ca
u
s
e
ad
d
itio
n
a
l
p
r
o
b
lem
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if
allo
w
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o
p
er
ate.
T
h
u
s
,
n
o
n
–
m
aj
o
r
s
w
er
e
co
n
f
r
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ted
w
it
h
a
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t
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f
“
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f
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”
d
u
r
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t
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e
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is
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s
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io
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A
n
a
l
y
z
in
g
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I
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o
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li
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ted
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se
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fe
c
ts
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rc
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rg
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.
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tag
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tag
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lt
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rtain
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ro
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m
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wa
re
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Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
E
R
E
I
SS
N:
2252
-
8822
Tea
ch
in
g
w
ith
S
o
cio
-
S
cien
tifi
c
I
s
s
u
es in
P
h
ysica
l S
cien
ce
:
T
ea
ch
er a
n
d
S
tu
d
e
n
ts
'
E
xp
erien
ce
s
(
Jo
y
Ta
len
s
)
279
w
it
h
t
h
e
h
elp
o
f
SS
I
.
On
t
h
e
o
th
er
h
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d
,
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d
e
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s
to
p
p
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k
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n
d
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e
p
r
o
ce
s
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b
ec
a
m
e
cr
itical
th
i
n
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m
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u
p
w
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th
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p
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if
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ted
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cie
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ical
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ate
citize
n
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.
Fig
u
r
e
5
s
h
o
w
s
th
a
t
teac
h
i
n
g
th
r
o
u
g
h
S
SI
a
m
o
n
g
n
o
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–
m
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a
P
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ical
Scie
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cl
ass
w
a
s
a
co
m
p
lica
ted
p
r
o
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s
s
.
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w
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e
r
,
if
teac
h
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s
w
ill
u
s
e
t
h
i
s
as
p
ar
t
o
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s
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ar
ticu
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s
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d
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t
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ad
v
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ta
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s
a
n
d
d
is
ad
v
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n
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o
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e
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s
h
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w
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d
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d
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a
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ass
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tai
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to
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ec
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a
w
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f
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d
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lo
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to
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t
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e
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s
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if
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ic
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lt
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s
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t
u
d
en
ts
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th
i
n
k
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e
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t
w
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at
h
ad
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e
en
d
is
cu
s
s
ed
in
t
h
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class
r
o
o
m
.
As
a
r
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lt
n
o
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-
m
aj
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r
s
w
ill
co
m
e
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p
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ith
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u
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b
ase
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ev
id
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o
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t
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iti
v
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d
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a
tiv
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e
f
f
ec
ts
o
f
s
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r
ce
s
o
f
e
n
er
g
y
.
Gr
ac
e
(
2
0
1
0
)
s
u
p
p
o
r
ted
th
e
ab
o
v
e
f
in
d
i
n
g
s
th
a
t
m
a
n
y
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s
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es
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ac
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m
o
d
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n
citize
n
s
ar
e
u
n
d
er
p
in
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ed
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y
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cie
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ce
m
a
k
i
n
g
m
an
y
p
eo
p
le
in
ter
es
ted
in
it
[1
6
]
.
I
t
is
also
w
o
r
th
y
to
co
n
s
id
er
t
h
at
t
h
ese
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s
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e
s
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c
h
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s
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o
f
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y
e
n
tail
s
ass
ess
m
en
t
o
f
r
i
s
k
s
w
h
ic
h
r
eq
u
i
r
es
citizen
s
to
m
a
k
e
s
o
u
n
d
j
u
d
g
m
en
t
in
e
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er
y
d
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is
io
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e
y
w
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m
a
k
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k
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id
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d
d
is
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v
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tag
e
s
o
f
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o
th
s
id
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T
h
u
s
,
m
a
y
p
eo
p
le
ar
e
f
o
cu
s
i
n
g
o
n
th
e
m
.
L
ik
e
wis
e,
SS
I
d
ev
elo
p
s
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a
w
ar
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ter
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b
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w
ee
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s
cie
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ce
an
d
s
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y
[
6
]
,
[
7
]
an
d
allo
w
s
s
t
u
d
en
ts
to
b
e
in
v
o
lv
ed
as a
cti
v
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ci
tizen
s
[
6
]
.
3
.
5
.
T
o
re
co
g
nize
t
he
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hica
l a
nd
m
o
ra
l i
m
p
lica
t
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ns
o
f
t
he
cho
ices t
ha
t
s
cience
o
f
f
er
s
f
o
r
a
ct
io
n
[
3
]
I
n
ter
m
s
o
f
co
n
s
eq
u
e
n
ce
s
,
s
o
m
e
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m
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r
s
s
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ar
ed
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h
at
S
SI
m
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d
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t
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n
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d
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n
th
e
P
h
ilip
p
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es
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l
as
th
e
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tag
e
s
an
d
d
is
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es.
Ot
h
er
s
co
m
m
e
n
ted
th
a
t
th
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w
er
e
“
in
fo
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med
a
b
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t
p
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r
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le
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.
A
n
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o
f
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co
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t
h
a
p
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ed
in
Min
d
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le
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o
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p
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n
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tr
u
ctio
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p
la
n
t
a
n
d
mem
b
ers
o
f
th
e
tr
ib
e
w
h
o
lived
in
th
e
s
ite
w
h
ere
th
e
s
a
id
p
o
w
er
p
la
n
t
w
ill
b
e
co
n
s
tr
u
cted
.
”
T
h
er
e
w
er
e
s
o
m
e
s
t
u
d
en
t
s
w
h
o
clai
m
ed
t
h
at:
“
w
e
r
ea
li
z
ed
th
a
t
a
ll
s
o
u
r
ce
s
o
f
en
erg
y
h
a
ve
th
eiro
w
n
a
d
va
n
ta
g
es
a
n
d
d
i
s
a
d
va
n
ta
g
es
w
h
ich
in
crea
s
ed
o
u
r
’
kn
o
w
led
g
e
b
ec
a
u
s
e
th
ere
w
eres
itu
a
tio
n
s
g
iven
in
e
a
ch
s
o
u
r
ce
.
”
On
e
s
tu
d
en
t
ad
d
ed
th
at
th
er
e
ar
e
is
s
u
es
t
h
at
p
e
r
tain
to
p
r
o
s
an
d
co
n
s
o
f
ea
ch
e
n
er
g
y
s
o
u
r
c
e
as
w
e
ll
a
s
p
o
s
s
ib
le
co
n
s
eq
u
e
n
ce
s
if
it
h
ad
b
ee
n
b
u
ilt in
a
n
y
co
u
n
tr
y
.
I
n
ter
m
s
o
f
s
tate,
t
h
er
e
w
er
e
s
tu
d
e
n
ts
,
w
h
o
e
x
p
r
ess
ed
d
is
ap
p
o
in
t
m
en
t
o
n
t
h
e
to
p
ic
b
e
ca
u
s
e
s
h
e
e
m
p
h
a
s
ized
th
at:
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d
e
s
p
ite
th
e
g
o
o
d
effec
ts
o
f
g
e
n
era
tin
g
en
erg
y,
its
n
eg
a
tive
s
id
e
s
u
ch
a
s
w
a
r
a
ls
o
h
a
p
p
e
n
ed
.
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is
co
n
tr
a
d
icted
th
e
fa
ct
th
a
t
s
o
u
r
ce
s
o
f
en
erg
y
s
h
o
u
ld
b
e
u
s
ed
fo
r
ev
eryb
o
d
y’
s
w
elfa
r
e
n
o
t
o
n
ly
fo
r
a
few
.
”
L
ik
e
w
is
e,
o
n
e
s
tu
d
en
t
s
h
ar
ed
th
at
s
h
e
w
a
s
w
o
n
d
e
r
in
g
w
h
y
g
e
n
er
atio
n
o
f
en
er
g
y
is
al
w
a
y
s
af
f
ec
ted
b
y
p
o
liti
ca
l
f
e
u
d
s
.
On
e
s
t
u
d
e
n
t
co
n
cl
u
d
ed
th
at
g
en
er
ati
n
g
en
er
g
y
i
s
d
o
n
e
f
o
r
th
e
g
o
o
d
o
f
all
h
o
w
ev
er
,
th
er
e
ar
e
a
lo
t o
f
p
r
o
b
lem
s
o
cc
u
r
in
p
lan
n
i
n
g
,
co
n
s
tr
u
cti
n
g
a
n
d
o
p
er
atin
g
p
o
w
er
p
lan
t.
B
ased
o
n
th
e
ex
p
er
ie
n
ce
s
o
f
th
e
teac
h
er
-
r
esear
c
h
er
,
n
o
n
-
m
aj
o
r
s
w
er
e
ab
le
to
an
al
y
ze
S
SI
th
r
o
u
g
h
w
h
at
t
h
e
y
lear
n
ed
in
cla
s
s
a
n
d
o
n
w
h
at
t
h
e
y
r
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d
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h
ed
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n
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h
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a
s
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t d
u
r
i
n
g
t
h
e
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is
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u
s
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n
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w
h
er
ei
n
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o
n
-
m
aj
o
r
s
ac
tiv
el
y
p
ar
ticip
ated
b
y
s
h
ar
in
g
t
h
eir
v
ie
w
s
o
n
t
h
e
ef
f
ec
ts
o
f
h
ar
n
ess
i
n
g
d
if
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er
e
n
t
s
o
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r
ce
s
o
f
e
n
er
g
y
s
u
ch
a
s
in
t
h
e
in
t
h
e
b
u
ild
i
n
g
o
r
co
n
s
tr
u
ct
io
n
o
f
d
a
m
s
.
S
tu
d
e
n
ts
e
x
p
r
ess
ed
th
eir
g
r
ief
w
h
e
n
m
an
y
p
eo
p
le
d
ied
w
h
en
a
d
a
m
co
llap
s
ed
.
T
h
e
y
w
er
e
also
u
p
s
et
w
it
h
t
h
e
e
f
f
ec
t
s
o
f
r
ad
i
atio
n
f
r
o
m
n
u
clea
r
p
o
w
er
p
lan
t
s
.
T
h
e
y
e
v
en
q
u
es
tio
n
ed
d
ec
is
io
n
o
v
er
to
o
m
u
c
h
d
ep
en
d
en
ce
o
n
f
o
s
s
i
l
f
u
el
a
s
s
o
u
r
ce
o
f
e
n
er
g
y
.
T
h
u
s
,
w
h
e
n
s
tu
d
e
n
ts
as
k
ed
to
r
an
k
th
e
d
if
f
er
en
t
s
o
u
r
ce
s
o
f
en
er
g
y
i
n
t
h
e
co
u
n
tr
y
,
it
w
as
o
b
s
er
v
ed
th
at
th
e
y
p
r
io
r
itize
h
u
m
a
n
w
el
f
ar
e
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d
t
h
e
en
v
ir
o
n
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e
n
t e
v
e
n
t
h
at
s
o
u
r
ce
is
to
o
ex
p
en
s
i
v
e.
Fig
u
r
e
6
s
h
o
w
s
t
h
at
s
t
u
d
en
ts
r
ea
lized
th
e
ad
v
a
n
tag
e
s
a
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d
d
is
ad
v
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g
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r
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n
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ar
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e
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i
n
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a
ce
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tain
s
o
u
r
ce
o
f
en
er
g
y
t
h
r
o
u
g
h
teac
h
in
g
S
SI
in
P
h
y
s
ica
l
Scien
ce
.
L
i
k
e
w
is
e,
t
h
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y
co
n
s
id
er
ed
th
e
p
o
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ib
le
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n
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eq
u
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ce
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ar
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s
i
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g
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ac
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er
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s
o
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r
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.
I
n
th
i
s
w
a
y
,
n
o
n
-
m
aj
o
r
s
w
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e
ab
le
to
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e
e
th
e
e
f
f
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ts
o
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ch
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er
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y
s
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r
ce
i
n
th
e
l
iv
e
s
o
f
p
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p
le
o
r
m
e
m
b
er
s
o
f
t
h
e
s
o
cie
t
y
.
Fig
u
r
e
6
.
Su
m
m
ar
y
o
f
a
x
ial
co
d
in
g
f
o
r
id
en
ti
f
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g
m
o
r
al
an
d
eth
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m
p
licatio
n
s
o
f
t
h
e
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s
u
e
Su
n
ar
an
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an
(
2
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c
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w
it
h
s
o
ciet
y
[
4
]
.
I
t
is
w
o
r
t
h
y
to
co
n
s
id
er
th
at
k
n
o
w
led
g
e
g
ain
ed
in
P
h
y
s
ical
Sc
ien
c
e
d
u
r
in
g
cla
s
s
r
o
o
m
d
is
cu
s
s
io
n
e
n
ab
led
s
t
u
d
en
t
s
to
s
ee
t
h
e
n
e
g
ati
v
e
a
n
d
p
o
s
itiv
e
s
id
es o
f
h
ar
n
e
s
s
i
n
g
ea
c
h
s
o
u
r
ce
o
f
en
er
g
y
.
On
th
e
o
th
er
h
a
n
d
,
w
h
e
n
S
SI
w
as
al
s
o
u
s
ed
i
n
t
h
e
cla
s
s
r
o
o
m
,
n
o
n
-
m
aj
o
r
s
‟
k
n
o
w
led
g
e
w
a
s
s
tr
en
g
t
h
e
n
ed
in
s
u
ch
a
w
a
y
t
h
at
co
n
cr
ete
s
ce
n
ar
io
s
w
er
e
g
i
v
en
.
T
h
is
p
r
o
v
es
t
h
at
th
is
is
r
ea
ll
y
h
ap
p
en
in
g
an
d
a
f
f
ec
tin
g
th
e
s
o
ciet
y
.
T
h
u
s
,
th
is
i
s
th
e
r
ea
s
o
n
w
h
y
t
h
e
s
tu
d
y
o
f
co
n
te
m
p
o
r
ar
y
s
o
ci
o
-
s
cie
n
ti
f
ic
is
s
u
e
s
(
SS
I
)
is
n
o
w
estab
li
s
h
ed
in
t
h
e
s
cien
ce
cu
r
r
ic
u
la
i
n
m
a
n
y
i
n
d
u
s
tr
ialized
co
u
n
tr
ie
s
[
3
]
b
ec
au
s
e
o
f
i
ts
p
o
ten
tial
f
o
r
cr
e
atin
g
a
m
o
r
e
r
ea
l,
h
u
m
a
n
e
i
m
a
g
e
o
f
s
cie
n
ti
f
ic
ac
tiv
it
y
an
d
f
o
r
p
r
o
m
o
ti
n
g
s
cien
ti
f
ic
liter
ac
y
[
5
]
.
A
d
d
itio
n
all
y
,
s
tu
d
e
n
ts
ar
e
in
ter
ested
in
w
o
r
k
i
n
g
w
it
h
co
m
p
lex
is
s
u
e
s
w
i
t
h
a
m
o
r
e
h
u
m
a
n
i
s
tic
p
er
s
p
ec
ti
v
e
.
T
h
is
h
ad
b
ee
n
o
b
s
er
v
ed
a
m
o
n
g
n
o
n
-
m
aj
o
r
s
w
h
en
t
h
e
y
d
i
s
cu
s
s
ed
ab
o
u
t
w
h
at
h
ap
p
en
ed
in
a
co
u
n
tr
y
w
h
er
e
a
d
a
m
w
as
b
u
il
t
an
d
it
s
u
d
d
en
l
y
co
llap
s
ed
w
h
e
n
th
e
d
a
m
s
tar
ted
to
o
p
er
ate.
3
.
6
.
B
a
s
ed
o
n t
he
a
s
s
u
m
ptio
n t
ha
t
w
ha
t
w
e
lea
rned
in s
cho
o
l c
a
n be
t
ra
ns
f
er
re
d t
o
ev
er
y
d
a
y
liv
in
g
[
3
]
I
n
ter
m
s
o
f
s
tate,
t
h
e
ar
ticl
es
f
o
r
an
al
y
zi
n
g
S
SI
m
ad
e
s
tu
d
en
ts
a
w
ar
e
o
n
s
o
u
r
ce
s
o
f
en
er
g
y
p
ar
ticu
lar
l
y
in
th
e
P
h
ilip
p
in
e
s
.
Fo
r
o
th
er
s
th
eir
k
n
o
w
led
g
e
o
n
t
h
e
to
p
ic
w
a
s
s
tr
en
g
t
h
en
ed
.
T
h
er
e
w
er
e
s
t
u
d
en
ts
w
h
o
co
m
m
en
ted
th
a
t
th
e
y
l
ea
r
n
ed
n
o
t
j
u
s
t
th
eo
r
ies
b
u
t
also
its
ap
p
licatio
n
in
r
ea
l
li
f
e.
So
m
e
s
t
u
d
en
ts
co
m
m
e
n
ted
t
h
at
t
h
e
y
i
m
a
g
i
n
e
d
th
in
g
s
th
at
ap
p
l
y
th
eo
r
ies
l
ea
r
n
ed
in
s
id
e
t
h
e
clas
s
r
o
o
m
.
On
e
s
t
u
d
en
t
ad
d
ed
th
at
th
e
i
s
s
u
es
w
er
e
r
ea
lis
tic
a
n
d
g
av
e
co
n
cr
ete
ex
p
la
n
atio
n
o
n
th
e
ad
v
an
tag
e
s
an
d
d
is
ad
v
an
tag
e
s
o
f
s
o
u
r
ce
s
o
f
en
er
g
y
to
o
r
g
a
n
is
m
s
i
n
th
is
p
lan
et.
T
h
er
e
w
er
e
s
t
u
d
en
ts
w
h
o
co
m
m
e
n
ted
“
I
ca
me
u
p
w
ith
a
lo
t
o
f
th
o
u
g
h
ts
a
fter
r
ea
d
in
g
th
e
a
r
ticle
s
,
r
ec
a
llin
g
th
e
d
is
cu
s
s
io
n
s
a
n
d
co
n
d
u
ctin
g
r
esea
r
ch
o
n
th
e
to
p
ic
o
n
a
lter
n
a
tiveso
u
r
ce
s
o
f
en
erg
y
a
n
d
h
o
w
to
h
a
r
n
ess
a
n
d
c
o
n
s
erve
th
em
.
”
A
s
t
u
d
en
t
cited
t
h
at:
”
th
r
o
u
g
h
S
S
I
m
y
kn
o
w
led
g
e
w
a
s
w
id
en
ed
n
o
t
ju
s
t
b
y
lea
r
n
in
g
a
b
o
u
t
s
o
u
r
c
es
o
f
en
erg
y
in
th
e
P
h
ilip
p
in
es
b
u
t
a
ls
o
a
r
o
u
n
d
w
o
r
ld
a
s
w
ell
a
s
its
a
d
va
n
ta
g
es
a
n
d
d
is
a
d
va
n
ta
g
es
a
n
d
i
ts
effec
ts
o
n
p
eo
p
le
a
n
d
en
v
ir
o
n
men
t.”
An
o
th
er
s
tu
d
e
n
t
w
h
o
s
h
ar
ed
th
at
t
h
e
k
n
o
w
led
g
e
o
b
tain
ed
is
v
er
y
u
s
ef
u
l
an
d
w
e
b
ec
a
m
e
a
w
ar
e
o
f
w
h
a
t
is
h
ap
p
en
i
n
g
ar
o
u
n
d
co
n
f
ir
m
s
th
i
s
.
T
h
is
is
co
n
f
ir
m
ed
b
y
o
n
e
s
t
u
d
en
t
wh
o
ex
p
lai
n
ed
t
h
at:
“b
efo
r
e
I
d
o
n
’
t
h
a
ve
a
n
y
id
ea
a
b
o
u
t
s
o
u
r
ce
s
o
f
en
erg
y
in
th
e
P
h
ilip
p
in
es
ev
en
in
o
u
r
n
eig
h
b
o
r
in
g
co
u
n
tr
ies
b
u
t
n
o
w
I
k
n
o
w
th
e
is
s
u
e
in
o
u
r
co
u
n
tr
ya
n
d
I
b
eliev
e
th
a
t
th
is
to
p
ic
i
s
t
r
u
ly
th
e
co
n
ce
r
n
o
f
ev
eryo
n
e
b
ec
a
u
s
e
ev
er
yo
n
e
is
co
n
s
u
min
g
en
erg
y
.
”
As
w
h
at
o
n
e
s
tu
d
e
n
t
co
n
f
ir
m
ed
th
at:
“
my
kn
o
w
led
g
e
o
n
s
o
u
r
ce
s
o
f
en
erg
y
w
a
s
s
tr
en
g
th
en
e
d
b
ec
a
u
s
e
w
h
en
I
r
ea
d
th
e
a
r
ticles
g
iven
,
th
ey
w
ere
n
o
t
fa
milia
r
to
me.
I
d
o
n
o
t
kn
o
w
th
a
t
th
ere
w
ere
is
s
u
es
like
th
ese.
I
a
mn
o
t
a
w
a
r
e
o
f
th
ese
a
r
ticles
.
I
t
ma
d
e
me
g
a
in
ed
mo
r
e
k
n
o
w
led
g
ea
b
o
u
t
o
u
r
co
u
n
tr
y
a
n
d
its
s
o
u
r
ce
s
o
f
en
erg
y.
”
I
n
ter
m
s
o
f
co
n
d
itio
n
,
t
h
e
n
o
n
-
m
aj
o
r
s
s
h
ar
ed
th
at
“p
r
io
r
kn
o
w
led
g
e
o
n
th
e
to
p
ic
h
elp
ed
a
lo
t
i
n
a
n
a
lyzi
n
g
th
e
s
o
cio
-
s
cien
tifi
c
is
s
u
es”
.
L
i
k
e
w
i
s
e,
a
s
t
u
d
en
t
ad
d
ed
“b
y
b
ei
n
g
a
w
a
r
e
o
n
s
o
u
r
ce
s
o
f
en
erg
y,
d
is
p
u
tes
a
n
d
a
r
g
u
men
ts
h
a
ve
b
ee
n
p
r
o
d
u
ce
d
b
y
th
e
co
n
flicts
a
b
o
u
t
th
e
is
s
u
es
in
th
e
a
r
tic
les”
.
I
n
r
elatio
n
to
th
is
,
a
s
t
u
d
en
t
e
m
p
h
a
s
ized
th
a
t
“th
o
u
g
h
s
o
me
in
fo
r
ma
tio
n
ma
y
n
o
t
b
e
d
ir
ec
tly
s
ta
ted
in
th
e
a
r
ticles,
o
n
e
ca
n
s
till
b
e
a
b
le
to
id
en
tify c
o
n
flicts
a
n
d
a
r
g
u
me
n
ts
”.
I
n
ter
m
s
o
f
co
n
s
eq
u
en
ce
s
,
m
an
y
s
t
u
d
en
t
s
“
b
ec
a
me
a
w
a
r
e
o
f
th
e
is
s
u
es
o
n
th
e
a
va
ila
b
ilit
y
o
f
r
eso
u
r
ce
s
.
”
T
h
er
e
ar
e
s
t
u
d
en
t
s
w
h
o
s
h
ar
ed
t
h
at
“
th
ey
a
ls
o
lea
r
n
ed
th
e
b
en
efits
a
n
d
p
o
s
s
ib
le
s
o
lu
tio
n
s
co
n
ce
r
n
in
g
s
o
u
r
ce
s
o
f
en
erg
y
in
th
e
c
o
u
n
tr
y”.
A
n
o
th
er
s
t
u
d
en
t
co
m
m
e
n
ted
th
a
t
“
I
g
a
in
ed
kn
o
w
led
g
e
a
b
o
u
t
s
o
u
r
ce
s
o
f
en
erg
y
-
I
lea
r
n
ed
h
o
w
it
w
o
r
ks
a
n
d
its
fu
n
ctio
n
s
a
n
d
t
h
e
a
d
va
n
t
a
g
es
a
n
d
d
is
a
d
va
n
ta
g
eso
f
t
h
e
s
a
id
to
p
ic.
Th
r
o
u
g
h
a
n
a
lyzi
n
g
S
S
I
,
it
g
ives
me
n
ewi
d
ea
a
b
o
u
t
th
e
less
o
n
o
n
en
erg
y
.
”
On
e
s
t
u
d
en
t
co
m
m
e
n
ted
th
a
t
“tea
ch
in
g
th
r
o
u
g
h
S
S
I
ke
p
t u
s
u
p
d
a
ted
in
a
ll th
e
is
s
u
es
a
b
o
u
t so
u
r
ce
s
o
f e
n
erg
y
a
n
d
w
h
a
t i
s
h
a
p
p
en
in
g
in
o
u
r
s
u
r
r
o
u
n
d
in
g
s
esp
ec
ia
lly
in
ter
ms o
f e
n
erg
y”.
T
h
is
s
tate
m
e
n
t
w
a
s
co
n
f
ir
m
ed
b
y
a
n
o
t
h
er
s
t
u
d
en
t
w
h
o
s
tated
th
a
t
“
tea
ch
in
g
th
r
o
u
g
h
S
S
I
is
r
ela
ted
to
r
ea
l
life
s
itu
a
tio
n
s
.
I
t
d
i
d
n
o
t
o
n
ly
g
ive
u
s
in
fo
r
ma
tio
n
b
u
t
a
ls
o
ma
d
e
u
s
a
w
a
r
e
o
f
th
e
cu
r
r
en
t
is
s
u
es
o
u
r
co
u
n
tr
y
is
fa
cin
g
r
ig
h
t
n
o
w
.
”
A
n
o
t
h
er
s
t
u
d
en
t
ag
r
ee
d
t
h
e
f
o
r
m
er
s
tate
m
e
n
t
b
y
s
a
y
i
n
g
th
at
“th
r
o
u
g
h
S
S
I
,
I
g
a
in
mo
r
e
kn
o
w
led
g
e
o
n
s
o
u
r
c
es
o
f
en
erg
y
a
n
d
t
h
e
is
s
u
es
r
ela
ted
to
it
w
h
ich
I
b
eliev
e
is
th
e
ma
in
to
p
ic
o
f
d
e
b
a
tes in
th
e
g
o
ve
r
n
men
t res
u
ltin
g
to
co
n
flict
.
”
I
n
te
r
m
s
o
f
m
ea
n
in
g
s
,
teac
h
i
n
g
s
o
cio
–
s
cie
n
ti
f
ic
is
s
u
es
f
o
r
n
o
n
-
m
aj
o
r
s
h
elp
ed
th
e
m
a
lo
t
i
n
lear
n
i
n
g
co
n
ce
p
ts
in
P
h
y
s
ical
Scie
n
ce
.
On
e
s
t
u
d
en
t
s
h
ar
ed
th
at
f
o
r
h
e
r
teac
h
in
g
SS
I
m
ea
n
s
:
“
a
n
ew
w
a
y
o
f
lea
r
n
in
g
a
less
o
n
in
P
h
ysica
l
S
cien
ce
p
a
r
ticu
la
r
l
y
s
o
u
r
ce
s
o
f
en
erg
y
t
h
a
t
is
n
o
t
co
n
fin
ed
in
w
h
a
t
i
s
w
r
itte
n
o
n
th
e
b
o
o
k
b
u
t
a
n
a
lyzi
n
g
a
n
d
r
eflec
tin
g
o
n
w
h
a
t
is
h
a
p
p
e
n
in
g
a
r
o
u
n
d
t
h
a
t
a
ffects
ev
ery
mem
b
er
o
f
th
e
s
o
ciety
.
”
A
n
o
t
h
er
s
tu
d
e
n
t
e
x
p
lain
ed
t
h
at
teac
h
i
n
g
SS
I
m
ea
n
s
t
h
at
“
a
n
a
lyzi
n
g
S
S
I
in
P
h
ysica
l
S
cien
ce
cla
s
s
mea
n
s
p
r
o
vid
in
g
ev
id
en
ce
o
n
w
h
a
t
s
tu
d
en
ts
l
ea
r
n
a
b
o
u
t
th
e
to
p
ic
like
s
o
u
r
ce
s
o
f
en
erg
y
th
r
o
u
g
h
p
u
ttin
g
to
g
eth
er
w
h
a
t
kn
o
w
led
g
e
o
n
e
g
a
in
e
d
o
n
th
e
to
p
ic
d
u
r
in
g
cla
s
s
r
o
o
m
d
is
c
u
s
s
io
n
a
n
d
w
h
a
t
o
n
elea
r
n
ed
w
h
ile
r
ea
d
in
g
a
n
d
a
n
a
lyzi
n
g
a
r
ticles r
ela
ted
to
th
e
to
p
ic
s
o
th
a
t stu
d
e
n
ts
ca
n
m
a
ke
a
ju
d
g
men
t o
r
s
ta
n
d
o
n
th
e
is
s
u
e.
”
T
h
e
teac
h
er
-
r
e
s
ea
r
ch
er
o
b
s
er
v
ed
th
at
in
teac
h
i
n
g
P
h
y
s
ical
S
cien
ce
p
ar
tic
u
lar
l
y
o
n
s
o
u
r
ce
s
o
f
e
n
er
g
y
th
r
o
u
g
h
SS
I
,
n
o
n
-
m
aj
o
r
s
b
ec
am
e
v
er
y
m
u
c
h
a
w
ar
e
o
n
w
h
a
t
is
h
ap
p
en
i
n
g
ar
o
u
n
d
t
h
e
m
i
n
clu
d
in
g
t
h
e
s
u
b
j
ec
ts
o
f
d
eb
ate
an
d
co
n
f
lict
s
w
h
ic
h
h
av
e
s
o
m
eth
in
g
to
d
o
w
it
h
e
n
er
g
y
.
T
h
is
i
s
s
o
b
ec
au
s
e
t
h
e
is
s
u
es
p
r
ese
n
ted
to
th
e
m
a
f
f
ec
t
t
h
e
m
s
el
v
es
i
n
o
n
e
w
a
y
o
r
an
o
t
h
er
as
s
tated
i
n
t
h
eir
ac
ti
v
it
y
w
h
er
ei
n
t
h
e
y
w
er
e
ask
ed
to
r
an
k
t
h
e
m
o
s
t
r
eliab
le
s
o
u
r
ce
o
f
en
er
g
y
in
th
e
co
u
n
tr
y
.
It
is
also
w
o
r
t
h
y
to
co
n
s
id
er
th
at
d
u
r
in
g
th
e
d
is
cu
s
s
io
n
,
s
tu
d
e
n
ts
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