Across
- 2. Gas people and cars release when they burn fuels.
- 5. When cars and factories release gases into the air.
- 6. Trash or smoke can make air dirty.
- 7. Energy that can run out, like coal and oil.
- 9. Energy that will not run out, like wind or solar.
Down
- 1. Coal, oil, and gas are examples of these fuels.
- 3. Paper, plastic, and bottles can be used again by doing this.
- 4. The layer of air that surrounds the Earth.
- 8. Power that turns on lights and machines.