Across
- 4. exchange of oxygen and carbon dioxide in living organisms
- 6. moving air
- 8. farmer’s friends
- 10. 78%of air
Down
- 1. layer of air around earth
- 2. a gaseous mixture
- 3. nitrogen of the air is used to manufacture this
- 5. supports combustion
- 7. dioxide component of air used by green plants to make their food
- 9. uses windpower to rotate