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There are 20 feet of blood vessels in each square inch of human skin.
Excessive alcohol use costs the country approximately $235 billion every year.
About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.
The horizontal fraction bar was introduced by the Arabs.
Thyroid conditions cause a higher risk of fibromyalgia and chronic fatigue syndrome.
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