Give two names of herbicides.

The delicate balance of $CO_2$ and $O_2$ is $NOT$ disturbed by:

For your agricultural field or garden,you have developed a compost-producing pit. Discuss the process in the light of bad odour,flies,and recycling of wastes for good produce.

$A$ water sample has $ppm$ level concentration of the following metals: $Fe = 0.2$,$Mn = 0.05$,$Cu = 3.0$,$Zn = 5.0$. The metal that makes the water sample unsuitable for drinking is

Which of the following does not cause atmospheric pollution?

Given below are two statements:
Statement $I$: An allotrope of oxygen is an important intermediate in the formation of reducing smog.
Statement $II$: Gases such as oxides of nitrogen and sulphur present in the troposphere contribute to the formation of photochemical smog.
In the light of the above statements,choose the correct answer from the options given below: