Across
- 4. Substance that causes pollution
- 5. Addition of pesticide can cause
- 6. also known as natural gas
- 8. .... gas required for photosynthesis
- 9. waste produced by plants or animals
- 10. celebrates on first July
Down
- 1. Retention of extra heat by the earth
- 2. can not be decomposed by organisms.
- 3. compressed natural gas
- 7. can cause noise pollution