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The horizontal fraction bar was introduced by the Arabs.
If you could remove all of your skin, it would weigh up to 5 pounds.
Cyanide works by making the human body unable to use oxygen.
The first documented use of surgical anesthesia in the United States was in Connecticut in 1844.
The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."
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