A ball of glass will bounce higher than a ball made of rubber.
73
Oak trees produce 2,200 acorns in a season, but each acorn only has a 1 in 10,000 chance of becoming an oak tree.
304
The average temperature at 40,000 feet above sea level is -60 F.
56
One cubic foot of gold weighs more than 1,200 pounds!
78
Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
Approximately 70 percent of the earth is covered by water. Only 1 percent of this water is drinkable.
65
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
Nearly 50% of the world's scientists are assigned to military projects.
71