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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."
There are 20 feet of blood vessels in each square inch of human skin.
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
Malaria was not eliminated in the United States until 1951. The term eliminated means that no new cases arise in a country for 3 years.
After 5 years of being diagnosed with rheumatoid arthritis, one every three patients will no longer be able to work.
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