1
-
Burning
of
fuels
.
2
-
Production
____________________
chemichals
.
3
-
Reactin
of
polluting
gases
____________________
water
in
clouds
.
4
-
Formation
of
sulphuric
____________________
nitric
acids
.
5
-
The
____________________
falls
as
acid
rain
.
6
-
Damage
____________________
the
environment
.