The earth is approx. 6,588,000,000,000,000,000 tons.
175
Diamonds can be shattered with a hammer.
-104
Research indicates that plants grow healthier when they are stroked.
173
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.
16
Scientists are learning from the 1700-year-old Lycurgus Cup, which changes colour thanks to nano particles.
0
One barrel of petroleum holds 42 gallons.
20