Unit 5 Week 3

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Across
  1. 1. one part in every hundred
  2. 3. created by burning fossil fuels
  3. 4. go all the way around the perimeter
  4. 9. a check or restraint on something
  5. 10. a new invention based on untested ideas.
  6. 11. coming before all others
  7. 12. measure or regulate
Down
  1. 2. three parts of one whole
  2. 5. fuel that won't run out
  3. 6. Equivalent to the sum of 6 and 7
  4. 7. one forth of a whole
  5. 8. introduction of harmful substances to the environment.
  6. 9. to give what is owed