Long Test

Edit Answers
12345678910111213
Across
  1. 3. subsystem
  2. 4. reaction
  3. 5. activities
  4. 7. of the earth
  5. 8. energy
  6. 11. hypothesis
  7. 12. operations
  8. 13. energy
Down
  1. 1. depletion
  2. 2. cycle
  3. 6. animals
  4. 9. matter
  5. 10. resources