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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 Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.
In 1864, the first barbiturate (barbituric acid) was synthesized.
The average adult has about 21 square feet of skin.
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