Exercise:
Primarily the greatest global threat of the present century is…
a) air pollution
b) water pollution
c) flood
d) climate change
Both the………..and manmade factors have contributed to climate change.
a) natural
b) artificial
c) cultural
d) anthropogenic
Without greenhouse effect the earth would be too………to live.
a) hot
b) cold
c) dark
d) humid
An increase in average temperature of earth is called……
a) global warming
b) climate
c) climate change
d) weather
The……..gases are good absorbers of earth’s radiation.
a) greenhouse
b) ozone
c) chlorofluorocarbons
d) noble
