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The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
The average office desk has 400 times more bacteria on it than a toilet.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
According to the FDA, adverse drug events harmed or killed approximately 1,200,000 people in the United States in the year 2015.
The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."
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