To solve the food problem of the country,which among the following is necessary?

Mohan and Virender were discussing the following problem: $A$ boy kicks a football high into the air. He runs and catches the football before it hits the ground. Which of the two,the boy or the football,has had greater displacement? Mohan was of the opinion that the football has travelled into the air and back,while the boy and the ball have covered the same displacement. Virender told him that it is not true. Both of them discussed and sorted the matter between them.
$(a)$ Who do you think is right,Mohan or Virender?
$(b)$ What are the values you see in Raman?

Name two types of animal feed and write their functions.

Fill in the blanks:
$(a)$ Photoperiod affects the . . . . . . .
$(b)$ Kharif crops are cultivated from . . . . . . to . . . . . . .
$(c)$ Rabi crops are cultivated from . . . . . . to . . . . . . .
$(d)$ Paddy,maize,green gram,and black gram are . . . . . . crops.
$(e)$ Wheat,gram,pea,and mustard are . . . . . . crops.

Discuss the role of hybridisation in crop improvement.

What do you mean by:
$(a)$ Blue revolution?
$(b)$ Yellow revolution?