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Asthma cases in Americans are about 75% higher today than they were in 1980.
The human body produces and destroys 15 million blood cells every second.
The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
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