environment

5. a person who doubts the truth or value of an idea or belief.
8. energy is produced using the sun, wind, etc., or from crops, rather than using fuels such as oil or coal.
9. changes in the world's weather, that it is believed to be getting warmer as a result of human activity
11. a gas that causes the greenhouse effect, especially carbon dioxide
12. produced when people drive their vehicles for personal use
13. a method of getting oil or gas from the rock below the surface of the ground by making large cracks in it.

1. a mixture of gases that surrounds any planet.
2. causing little or no damage to the environment and therefore able to continue for a long time.
3. comes from industries production of goods and services that we consume
4. fuels, such as gas, coal, and oil, that were formed underground from plant and animal remains millions of years ago
6. an increase in the amount of carbon dioxide and other gases in the atmosphere is believed to be the cause of a gradual warming of the surface of the earth
7. a gradual increase in world temperatures caused by gases such as carbon dioxide
10. someone who publicly supports something.