One 75-watt bulb gives more light than three 25-watt bulbs.
57
The Earth's atmosphere weighs about 5.5 quadrillion tons.
108
In zero gravity, a candle's flame is round and blue.
16
Scientists concluded that the chicken came first, not the egg, because the protein which makes the egg shells is only produced by hens.
11
Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
The bark of an older redwood tree is fireproof.
65
At room temperature, the average air molecule travels at the speed of a rifle bullet.
55
Nearly 50% of the world's scientists are assigned to military projects.
71