e
l
o
p
m
e
n
t
o
f
c
r
o
w
d
e
d
i
n
d
u
s
t
r
i
a
l
c
i
t
i
e
s
w
h
i
t
c
h
p
u
t
h
u
g
e
a
m
o
u
n
t
s
o
f
p
o
l
l
u
t
a
n
s
i
n
t
o
s
m
a
l
l
a
r
e
a
s
,
t
h
e
p
r
o
b
l
e
m
h
a
s
b
e
c
o
m
e
m
o
r
e
i
m
p
o
r
t
a
n
t
.
A
u
t
o
m
o
b
i
l
e
s
a
n
d
o
t
h
e
r
n
e
w
i
n
v
e
n
t
i
o
n
s
m
a
k
e
p
o
l
l
u
t
i
o
n
s
t
e
Страницы: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29
