Neanderthal man had a brain capacity 100cc larger than modern man's.
50
Indoor pollution is 10 times more toxic than outdoor pollution.
62
One 75-watt bulb gives more light than three 25-watt bulbs.
57
Iron weighs more after it rusts.
68
One cubic foot of gold weighs more than 1,200 pounds!
78
Aluminum used to be more valuable than gold!
84
The Earth's atmosphere weighs about 5.5 quadrillion tons.
108