The average temperature at 40,000 feet above sea level is -60 F.
56
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310
A single cup of gasoline, when ignited, has the same explosive power as five sticks of dynamite.
57
In 1999, Harvard physicist Lene Hau was able to slow down light to 17 meters per second and in 2001, was able to stop light completely.
39
Indoor pollution is 10 times more toxic than outdoor pollution.
62
Iron weighs more after it rusts.
16
Each day, up to 150 species of life become extinct.
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