When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Pumice is the only rock that floats on water.
14
Indoor pollution is 10 times more toxic than outdoor pollution.
62
Neanderthal man had a brain capacity 100cc larger than modern man's.
50
Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
Nylon is made from coal and petroleum.
42
Billions of neutrinos pass unnoticed through your body every second.
6
A single speck of dust is half way in size between a subatomic particle and the Earth.
15