Across
- 4. The layer of the atmosphere that protects us from the sun
- 6. Sources from nature that are NOT easy and quick to replace
- 7. Gases in the air that trap heat and make the Earth warmer
- 8. Harmful gases or smoke
Down
- 1. The destruction of forests
- 2. Sources from nature that are easy and quick to replace
- 3. To set on fire
- 5. The burning of coal, oil, or gas to create energy