Did you know?

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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Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.

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The immune system needs 9.5 hours of sleep in total darkness to recharge completely.

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Nearly 31 million adults in America have a total cholesterol level that is more than 240 mg per dL.

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The human body produces and destroys 15 million blood cells every second.

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