Across
- 2. Its atomic number is 82
- 3. caused by industrial air pollution and transportation.
- 7. an agency that protects the environment.
- 9. the destruction and moving of soil.
- 11. used to promote plant growth.
- 12. 1 carbon and 2 oxygen atoms.
- 13. A large part of ground erosion and deforestation
- 15. A way of farming or a hill and preventing soil loss
- 17. mid-west in america, dust blown by wind.
- 18. A period with little to no water
- 19. particles carried from construction.
- 20. its atomic number is 16.
Down
- 1. used to kill bugs.
- 4. a layer of the atmosphere and a toxic molecule.
- 5. humans on Earth.
- 6. to maintain something at a certain level
- 8. water found under ground.
- 10. used to kill plants.
- 14. factories and other mechanical production facilities.
- 16. its atomic number is 80.