$DDT$ is

The compound that is $NOT$ a common component of photochemical smog is

Which of the following is harmful to calcium-containing structures and is responsible for causing cough and throat irritation in humans?

The two strong acids present in the acid rain are

The water quality of a pond was analysed and its $BOD$ was found to be $4$. The pond has

On the surface of polar stratospheric clouds,hydrolysis of chlorine nitrate $(ClONO_2)$ gives $A$ and $B$,while its reaction with $HCl$ produces $B$ and $C$. $A, B$ and $C$ are,respectively: