The bark of an older redwood tree is fireproof.
65
One 75-watt bulb gives more light than three 25-watt bulbs.
57
One barrel of petroleum holds 42 gallons.
20
Cold water weighs more than hot water.
93
A single speck of dust is half way in size between a subatomic particle and the Earth.
15
Scientists have developed a microparticle filled with oxygen that can be injected into the blood stream, enabling us to live without breathing.
21