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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.
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.
About 100 new prescription or over-the-counter drugs come into the U.S. market every year.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
On average, someone in the United States has a stroke about every 40 seconds. This is about 795,000 people per year.
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