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