The gaseous envelope around the earth is known as the atmosphere. The lowest layer of this extends up to $10 \ km$ from sea level; this layer is $.......$

The incorrect statement$(s)$ among $(a) - (d)$ regarding acid rain is (are) :
$(a)$ It can corrode water pipes.
$(b)$ It can damage structures made up of stone.
$(c)$ It cannot cause respiratory ailments in animals.
$(d)$ It is not harmful for trees.

In drinking water,if the maximum prescribed concentration of copper is $x \ mg \ dm^{-3}$,the maximum prescribed concentration of zinc will be

Global warming is due to an increase of:

$ODS$ is used in .....

State whether the following statements are true or false:
$(1)$ Mist is produced by particles of spread liquid and by condensation of vapour in air.
$(2)$ Particulate matter of size up to $5 \ \mu m$ reaches directly into the lungs.
$(3)$ Ozone and nitric oxide cause irritation in the nose and throat.