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There are 20 feet of blood vessels in each square inch of human skin.
The familiar sounds of your heart are made by the heart's valves as they open and close.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
Women are 50% to 75% more likely than men to experience an adverse drug reaction.
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
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