Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
The Earth's atmosphere weighs about 5.5 quadrillion tons.
108
Neanderthal man had a brain capacity 100cc larger than modern man's.
50
German chemists made a replica of a trophy the size of one molecule.
68
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
In Arizona, a solar wind energy tower has been proposed that would generate as much energy as the Hoover Dam.
5
