The horizontal fraction bar was introduced by the Arabs.
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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.
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The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
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If you could remove all of your skin, it would weigh up to 5 pounds.
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Chronic marijuana use can damage the white blood cells and reduce the immune system's ability to respond to disease by as much as 40%. Without a strong immune system, the body is vulnerable to all kinds of degenerative and infectious diseases.
