A cubic yard of air weighs about 2 pounds at sea level.
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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
The banana plant cannot reproduce itself. It can be propagated only by the hand of man.
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Sound travels about 4 times faster in water than in air.
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0.3% of solar energy from the Sahara is enough to power the whole of Europe.
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One barrel of petroleum holds 42 gallons.
20
Airports that are at higher altitudes require a longer airstrip due to lower air density.
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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!
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