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Though the United States has largely rejected the metric system, it is used for currency, as in 100 pennies = 1 dollar. Previously, the British currency system was used, with measurements such as 12 pence to the shilling, and 20 shillings to the pound.
There are more sensory neurons in the tongue than in any other part of the body.
Each year in the United States, there are approximately six million pregnancies. This means that at any one time, about 4% of women in the United States are pregnant.
There are 20 feet of blood vessels in each square inch of human skin.
Hippocrates noted that blood separates into four differently colored liquids when removed from the body and examined: a pure red liquid mixed with white liquid material with a yellow-colored froth at the top and a black substance that settles underneath; he named these the four humors (for blood, phlegm, yellow bile, and black bile).
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![The mortality rate in the United States increases with age and is lower for women than men at every ...](https://biology-forums.com/gallery/47/medium_667187_21_02_17_6_13_00_256181578.jpeg)