Which of the following gases make up for most of the air?
Carbon dioxide
Hydrogen
Nitrogen
Oxygen
Electric wires are usually made of
Aluminium
Magnesium
Copper
Silver
Which of the following does not cause air pollution?
Carbon monoxide emitted from exhaust pipes of vehicles.
Pesticides washed into rivers by the rain.
Fogs caused by forest fires.
Smoke from factories.
The table below groups some sources of pollution.
Which group causes air pollution?
I
II
III
IV
Many cars today are designed to get better gas mileage than those made in the past. This change resulted from a need to
Recycle materials
Improve safety
Produce chemicals
Conserve resources