Across
- 2. cheap to cut down and easy to use as fuel
- 4. partially decomposed organic matter
- 5. burned to heat water and create steam
- 8. can be replenished naturally and is reusable
- 9. easily accessible and often used in developing countries
- 10. world's largest oil sands reserve
Down
- 1. cannot be replenished naturally and exist in fixed amounts
- 3. what natural gas is mostly made of
- 6. what burning biomass releases
- 7. combination of clay, sand, water, and bitumen