In agricultural practices,higher input gives higher yield. Discuss how?

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?

When Ashok visited his village,he observed that villagers were suffering from malnutrition. To curb malnutrition in the village,he suggested they select five or six fish species in a pond. This increased the fish yield from the pond. The villagers were surprised to see the results and asked him to help with the other two ponds in the village.
$(i)$ What name is given to this intensive fish farming?
$(ii)$ Write the basis on which the different fish species are selected.
$(iii)$ Ashok's initiative is worth praising. Give two reasons.

How does catla differ from mrigal?

Raman along with his family visited the Dead Sea. There,his father observed a lady lying on her back in the sea and reading a newspaper. This astonished Raman's father,who thought the lady might be practicing black magic. Raman explained to his father why the lady was not drowning.
$(a)$ What,according to you,is the reason the lady is not drowning in the Dead Sea?
$(b)$ What value is exhibited by Raman?

$(i)$ State three ways by which pests attack plants.
$(ii)$ Name the chemicals used to control pests.
$(iii)$ Explain why excessive use of such chemicals should be avoided.