Nylon is made from coal and petroleum.
42
German chemists made a replica of a trophy the size of one molecule.
68
In Arizona, a solar wind energy tower has been proposed that would generate as much energy as the Hoover Dam.
5
A single speck of dust is half way in size between a subatomic particle and the Earth.
15
Sound travels about 4 times faster in water than in air.
408
