Give any two ways in which non-biodegradable substances would affect the environment.

What is ozone and how does it affect any ecosystem?

Which of the following groups contain only biodegradable items?

1. Grass, flowers and leather
2. Grass, wood and plastic
3. Fruit-peels, cake and lime-juice
4. Cake, wood and grass

Which of the following constitute a food-chain?

1. Grass, wheat and mango
2. Grass, goat and human
3. Goat, cow and elephant
4. Grass, fish and goat