When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Most dust particles in your house come from dead skin.
48
One barrel of petroleum holds 42 gallons.
20
Approximately 70 percent of the earth is covered by water. Only 1 percent of this water is drinkable.
65
In Arizona, a solar wind energy tower has been proposed that would generate as much energy as the Hoover Dam.
5
The weight of a carat (200 milligrams), standard unit of measurement for gemstones, is based on the weight of the carob seed.
51
Every day, plants convert sunlight into energy equivalent to six times the entire power consumption of human civilization.
9