The average temperature at 40,000 feet above sea level is -60 F.
56
The hair of an adult man or woman can stretch 25 percent of its length without breaking.
116
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
The only letter not appearing on the Periodic Table is the letter "J".
180
Scientists aren't sure what color dinosaurs were.
312
One 75-watt bulb gives more light than three 25-watt bulbs.
57
Sound travels about 4 times faster in water than in air.
408