Mathway.com solves all kinds of math homework problems with step by step explanations.
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By weight, Bone is five times stronger than steel.
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All humans have the ability to see ultraviolet light, but it is passively filtered out by the eye's lens. People who undergo surgery to remove the lens can detect ultraviolet light.
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Passengers on the Beijing subway can pay with plastic bottles.
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Leonardo da Vinci could write with one hand and draw with the other at the same time.
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