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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.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
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