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The average office desk has 400 times more bacteria on it than a toilet.
After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
The most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.
Vaccines prevent between 2.5 and 4 million deaths every year.
The horizontal fraction bar was introduced by the Arabs.
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