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Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
The heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
The average office desk has 400 times more bacteria on it than a toilet.
Asthma cases in Americans are about 75% higher today than they were in 1980.
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