Cataract and skin cancer are caused by

Green chemistry refers to reactions which . . . . . .

Which of the following is wrong with respect to our responsibility as a human being to protect our environment?

The pollution due to oxides of sulphur gets enhanced due to the presence of:
$(a)$ particulate matter
$(b)$ ozone
$(c)$ hydrocarbons
$(d)$ hydrogen peroxide
Choose the most appropriate answer from the options given below:

The stratosphere extends from sea level up to an altitude of $...$ kilometers.

How is nitrogen oxide formed in the atmosphere,and why is an excessive amount of nitrogen oxide harmful?