The smell of freshly cut grass is actually a plant distress call.
31
Pumice is the only rock that floats on water.
14
Iron weighs more after it rusts.
68
A single speck of dust is half way in size between a subatomic particle and the Earth.
15
The only letter not appearing on the Periodic Table is the letter "J".
180
Each day, up to 150 species of life become extinct.
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