Natural Resources

123456789
Across
  1. 3. Food made by green plants
  2. 5. A gas released from decomposition of organic matter
  3. 6. The elemental form of carbon dioxide
  4. 7. A layer of air that traps UV rays of the Sun
  5. 9. The outer most layer of the Earth
Down
  1. 1. A solid black substance formed from dead plants
  2. 2. The process which releases CO2 gas and smoke
  3. 4. The form of Nitrogen that can be used by plants
  4. 8. Major constituent of atmosphere