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About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.
The average adult has about 21 square feet of skin.
Nearly 31 million adults in America have a total cholesterol level that is more than 240 mg per dL.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
On average, the stomach produces 2 L of hydrochloric acid per day.
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