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Nearly 31 million adults in America have a total cholesterol level that is more than 240 mg per dL.
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.
On average, the stomach produces 2 L of hydrochloric acid per day.
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.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
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