The Earth's atmosphere weighs about 5.5 quadrillion tons.
108
One 75-watt bulb gives more light than three 25-watt bulbs.
57
The bark of an older redwood tree is fireproof.
65
The only letter not appearing on the Periodic Table is the letter "J".
180
Sound travels about 4 times faster in water than in air.
408
The average temperature at 40,000 feet above sea level is -60 F.
56
Research indicates that plants grow healthier when they are stroked.
173