The timetable below shows history of some of the major energy sources we depend on in the United States. (click the timetable to enlarge it if necessary)

1. How many years ago was nuclear power first used to generate electricity in our country?
2. How many years difference is there between the year when oil was first discovered in this country and the year when natural gas was first used for street lamps?
3. How many years did it take to use wind energy for generating electricity after the first wind mill was constructed for pumping water?
4. How many years did it take to use coal for generating electricity after coal was first discovered in this country?

Sources: EIA energy KIDS

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