Across
- 2. What gas do animals breathe?
- 5. What gas makes up most of healthy air?
- 6. Air pollution can be caused by cutting down ...
- 7. What pollutant is produced when volcanoes erupt?
Down
- 1. What pollutant is produced from farming animals?
- 3. What is the name of tiny pieces of plastic that can float in the air?
- 4. Having more people in each car produces _____ pollution