The Earth's atmosphere weighs about 5.5 quadrillion tons.
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According to studies, men change their minds two to three times more often than women.
72
Scientists have developed a microparticle filled with oxygen that can be injected into the blood stream, enabling us to live without breathing.
21
Pumice is the only rock that floats on water.
14
Only 12,000 years ago there was a species closely related to modern humans called Homo floresiensis that had been living on an Indonesian Island. They used fire and rather advanced tools, yet were only about 3 feet tall and weighed around 25kg.
15
Nearly 50% of the world's scientists are assigned to military projects.
71