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Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.
Asthma occurs in one in 11 children and in one in 12 adults. African Americans and Latinos have a higher risk for developing asthma than other groups.
In 1864, the first barbiturate (barbituric acid) was synthesized.
There are approximately 3 million unintended pregnancies in the United States each year.
The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
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