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Approximately 500,000 babies are born each year in the United States to teenage mothers.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
Your heart beats over 36 million times a year.
Asthma is the most common chronic childhood disease in the world. Most children who develop asthma have symptoms before they are 5 years old.
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