4.5 pounds of sunlight strike the Earth each day.
27
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310
Nearly 50% of the world's scientists are assigned to military projects.
71
The average temperature at 40,000 feet above sea level is -60 F.
56
Sound travels fifteen times faster through steel than through air.
134
Scientists in Germany have developed a candy that doesn't cause cavities.
11