Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
Oak trees produce 2,200 acorns in a season, but each acorn only has a 1 in 10,000 chance of becoming an oak tree.
304
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
At room temperature, the average air molecule travels at the speed of a rifle bullet.
55
A coal power station puts 100 times more radiation into the air than a nuclear power plant producing the same amount of energy.
7
Columbia University has developed an artificial tree that passively soaks up carbon dioxide from the air using "leaves" that are 1,000 times more efficient than true leaves that use photosynthesis.
15
For every gallon of sea water, you get more than a quarter pound of salt.
45