The bark of an older redwood tree is fireproof.
65
Balsa wood is classified as a hard wood!
41
In Arizona, a solar wind energy tower has been proposed that would generate as much energy as the Hoover Dam.
5
Only 12,000 years ago there was a species closely related to modern humans called Homo floresiensis that had been living on an Indonesian Island. They used fire and rather advanced tools, yet were only about 3 feet tall and weighed around 25kg.
15
The average temperature at 40,000 feet above sea level is -60 F.
56
One ragweed plant can release as many as one billion grains of pollen!
51
Indoor pollution is 10 times more toxic than outdoor pollution.
62