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Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.
There are 20 feet of blood vessels in each square inch of human skin.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Approximately 70% of expectant mothers report experiencing some symptoms of morning sickness during the first trimester of pregnancy.
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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