Write a note on biogas.

Write a note an solar cells.

Write a note an wind energy.

Explain the waste water treatment process.

A family has 3 three cars and can afford to buy fuel. They prefer to go out independently. Is it right to suggest car pooling for such people. Justify.

How does rainwater harvesting structures recharge ground water?

How will you prevent soil erosion?

What are the consequences of soil erosion?

Why is the management of forest and wildlife resource considered as a challenging task?

Although coal and petroleum are produced by degradation of biomass, yet we need to conserve them. Why?