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

Distinguish between intercropping and mixed cropping. List any two advantages of intercropping over mixed cropping.

Give two examples of milch animals.

$(i)$ 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.

List two desirable traits for fodder crops.

The number of dengue cases has increased in Sana's village in the last one year. She read in her textbook that diseases like dengue spread through mosquitoes which breed in stagnant water. She immediately suggested to her friends that they should kill the mosquitoes in water bodies in the locality. They also took the help of the nearest municipal office.
$(a)$ Which preventive measures do you suggest for the prevention of such diseases caused by mosquitoes? Mention any two measures.
$(b)$ Which values are displayed by Sana in taking this initiative?
$(c)$ Suggest one school activity to promote such values in school students.