Review For 2nd Quarterly

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Across
  1. 1. Precipitation
  2. 6. Closest layer of the atmosphere to the earth.
  3. 7. The combination of the sea and nitrogen.
  4. 8. Burning.
  5. 12. The 4th layer of the atmosphere.
  6. 14. The nitrogen that is in the atmosphere.
  7. 15. Too much fertilizer.
Down
  1. 2. The height from sea level.
  2. 3. Turning free nitrogen into nitrogen that can be used by living organisms.
  3. 4. Breathing.
  4. 5. Animal waste.
  5. 9. When nitrogen leaves the atmosphere.
  6. 10. When a corpse gives its nitrogen to the atmosphere or the ground.
  7. 11. The 3rd layer of the atmosphere
  8. 13. What turtles use to make their shells.