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Illicit drug use costs the United States approximately $181 billion every year.
If all the neurons in the human body were lined up, they would stretch more than 600 miles.
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 adult has about 21 square feet of skin.
Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.
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