Across
- 3. a change in the earth's weather conditions
- 7. a situation in which different things are equal
- 8. gases or other substances that are sent into the atmosphere
- 9. a gas without smell or colour, often used as a fuel
- 10. thick forest that grows in the hot parts of the world
Down
- 1. things that exist in nature and can be used by people
- 2. damage caused to water,air,...by harmful substances or waste
- 4. the protection of the natural environment
- 5. a group of animals or plants that have similar characteristics
- 6. a chemical substance found in all living things