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The horizontal fraction bar was introduced by the Arabs.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
If you could remove all of your skin, it would weigh up to 5 pounds.
Elderly adults are living longer, and causes of death are shifting. At the same time, autopsy rates are at or near their lowest in history.
The familiar sounds of your heart are made by the heart's valves as they open and close.
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