Energy from supply about 70 percent of the generation of electricity in the united states. (2 words)

Fossil Fuels
 "Fossil Fuels" are natural fuels such as petroleum, gas, and coal and are used to generate energy. They are hydrocarbon deposits which are created from living organisms. Fossil Fuels are formed over thousands of years from the remains of ancient plants and animals. They also have a high hydrogen and carbon content and are preserved in rocks in the earth's crust. Coal mainly consists of carbon, while petroleum consists mainly of hydrogens. Natural gas is a fossil fuel in a gaseous state. 

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