Across
- 4. to make fertilisers,dyes and explosives
- 5. helps to regulate the Earth's temperature
- 7. The cycle that starts from the soil
Down
- 1. a way of reusing carbon atoms
- 2. The cycle with water
- 3. a mineral that makes up 1% of a person's total body weight
- 6. colorless, odorless, non-toxic, and highly combustible