Enamel is hardest substance in the human body.
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			For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
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			The human body contains over a billion miles of DNA.
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			Your heart will pump about 212 million liters in its lifetime.
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			Yawns are more contagious among people with closer relationships.
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			Chewing gum boosts your brain power.
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			Your thumb is about the same size as your nose.
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			It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
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