Across
- 2. The type of fuel humans depend on most. It is non renewable and found underground.
- 5. energy The most abundant energy source capable of being harnessed by humans.
- 6. layer The part of Earths atmosphere that repels the suns ultraviolet rays.
- 7. The most common green house gas.Humans breathe it out and trees consume it.
- 8. Energy that can be used and reused an infinite number of times.
- 9. The name given to gases that trap heat and cause global warming.
- 10. Living within the limits of Earths natural resources
Down
- 1. The most efficient form of transportation in terms of energy usage. It does not pollute.
- 3. The term given to food sold in supermarkets and grown or fed without synthetic fertilizers, chemicals, hormones and antibiotics.
- 4. A tool used to illustrate how much a human being has on Earth.