Brass doorknobs automatically disinfect themselves in about 8 hours.
18
The banana plant cannot reproduce itself. It can be propagated only by the hand of man.
155
A coal power station puts 100 times more radiation into the air than a nuclear power plant producing the same amount of energy.
7
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
A single speck of dust is half way in size between a subatomic particle and the Earth.
15
Iron weighs more after it rusts.
68
Sound travels about 4 times faster in water than in air.
408