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On average, someone in the United States has a stroke about every 40 seconds. This is about 795,000 people per year.
The most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.
The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
On average, the stomach produces 2 L of hydrochloric acid per day.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
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