It’s thought that about three billion people around the world cannot use electricity. Instead of electric lights they use things like kerosene lamps, but these are inconvenient and can make the air dirty.
Now, let’s try a quiz!
What energy source doesn’t make the air dirty and doesn’t disappear no matter how much you use it?
A. Coal
B. Solar
C. Oil
Next, try the quiz and pick the answers you think are correct.
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