When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
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The gas that gives rotten eggs their distinctive foul smell may slow ageing and block damaging chemical reactions inside cells, according to scientists in China.
5
Balsa wood is classified as a hard wood!
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Pure water (H2O) does not conduct electricity on its own.
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During photosynthesis, plants emit light humans can’t see, but NASA can see that light from space - and they've even made maps of it!
21
The weight of a carat (200 milligrams), standard unit of measurement for gemstones, is based on the weight of the carob seed.
51
One gallon of used motor oil can ruin approximately one million gallons of fresh water!
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Marie Curie, the Nobel prize winning scientist who discovered radium, died of radiation poisoning.
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