When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
The Earth's atmosphere weighs about 5.5 quadrillion tons.
108
Nylon is made from coal and petroleum.
42
The bark of an older redwood tree is fireproof.
65
Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
Most liquid laundry detergents are alive with living organisms that help to break down stains!
88
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310