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During the twentieth century, a variant of the metric system was used in Russia and France in which the base unit of mass was the tonne. Instead of kilograms, this system used millitonnes (mt).
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More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.
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According to the CDC, approximately 31.7% of the U.S. population has high low-density lipoprotein (LDL) or "bad cholesterol" levels.
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The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
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The heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.