In 1976, an underachieving Princeton junior undergraduate wrote a term paper detailing how to make a nuclear bomb. He got an "A", but never got his paper back because it was seized by the FBI.
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In the mid-90’s, Coca Cola recalled an advertising poster due to a hidden sexual image.
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The Sun and Moon appear to be the same size because the moon is 400 times smaller than the Sun, but 400 times closer to Earth.
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