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

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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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Vaccines prevent between 2.5 and 4 million deaths every year.

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After 5 years of being diagnosed with rheumatoid arthritis, one every three patients will no longer be able to work.

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It is believed that humans initially contracted crabs from gorillas about 3 million years ago from either sleeping in gorilla nests or eating the apes.

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