A cubic yard of air weighs about 2 pounds at sea level.
31
Scientists aren't sure what color dinosaurs were.
312
The bark of an older redwood tree is fireproof.
65
Iron weighs more after it rusts.
16
A cesium atom in an atomic clock beats over nine billion times a second.
43
The most expensive material on the planet is antimatter - worth $62.5 trillion per gram.
18
Forensic scientists can determine a person's sex, age, and race by examining a single strand of hair.
101
One ragweed plant can release as many as one billion grains of pollen!
51