Biological pollution in water is caused by

• Coal mines

• domestic sewage and animal excreta

• oil spills

• chemicals like paint

Clear, transparent water is always fit for drinking. Comment.

You are a member of the municipal body of your town.
Make a list of measures that would help your town to ensure the supply of clean water to all its residents.

Explain the differences between pure air and polluted air.

Explain circumstances leading to acid rain. How does acid rain affect us?

Which of the following is not a greenhouse gas?

Describe the ‘Green House Effect’ in your own words.

Prepare a brief speech on global warming. You have to deliver the speech in your class.

Describe the threat to the beauty of the Taj Mahal.

Why does the increased level of nutrients in the water affect the survival of aquatic organisms?

What are the main causes of smoke?