Fossil Energy

6. the production and discharge of gas or radiation.
8. a device, as in a furnace, stove, or gas lamp, that is lit to produce a flame.
9. an oily mixture of hydrocarbons that can be extracted from layers of rock and used to produce fuel.
11. a substance or condition that contaminates air, water, or soil.

1. funds or material set aside or saved for future use.
2. a chemical element found in the air as a colorless odorless tasteless gas that is necessary for life.
3. the degree of compactness of a substance.
4. the process of burning something.
5. the application of scientific knowledge for practical purposes, especially in industry.
7. a complete list of goods in stock or other contents.
10. the remains or impression of a prehistoric organism.
12. soft, finely stratified sedimentary rock that formed from consolidated mud or clay.