Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
A coal power station puts 100 times more radiation into the air than a nuclear power plant producing the same amount of energy.
7
Scientists aren't sure what color dinosaurs were.
312
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
One barrel of petroleum holds 42 gallons.
20
Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
One third of the electricity produced on earth is used to power electric light bulbs!
75