The major groups of activities for improving crop yields can be classified as:

How is a fumigant different from a pesticide? Name one natural substance which can be used in place of a fumigant.

Distinguish between:
$(i)$ Inland fishery and marine fishery.
$(ii)$ Culture fishery and capture fishery.
$(iii)$ Apiculture and aquaculture.

Suggest some preventive measures for the diseases of poultry birds.

Two friends,Girish and Neeraj,were discussing Newton's third law. They were perplexed about how action and reaction are equal and opposite. They could not think of an experiment by which they could ascertain this fact. Pushkar,who was their friend,told them that he would set up an experiment to prove this to them. By performing an experiment,Pushkar demonstrated the law.
$(a)$ Can you think of an experiment by which you can demonstrate this law?
$(b)$ What values do you think Pushkar has?

What are those crops called which are grown in the winter season?