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The average office desk has 400 times more bacteria on it than a toilet.
Human kidneys will clean about 1 million gallons of blood in an average lifetime.
Today, nearly 8 out of 10 pregnant women living with HIV (about 1.1 million), receive antiretrovirals.
Vaccines prevent between 2.5 and 4 million deaths every year.
The horizontal fraction bar was introduced by the Arabs.
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