Which is the main component responsible for acid rain in the atmosphere?

Identify the types of smog that are oxidizing and reducing in nature.

The acids responsible for acid rain are ......... .

Among the following compounds,which one is not responsible for the depletion of ozone layer?

State the harmful effects of excessive production of sulfur oxide.

Fill in the blanks:
$(1)$ Deficiency of fluoride is responsible for ............. .
$(2)$ The upper limit of lead concentration in drinking water is ............. .
$(3)$ The maximum limit of nitrate in drinking water is ............. .
$(4)$ ............. and ............. chemicals act as poisons for the nervous system.