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If you could remove all of your skin, it would weigh up to 5 pounds.
The average adult has about 21 square feet of skin.
There are approximately 3 million unintended pregnancies in the United States each year.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
Asthma cases in Americans are about 75% higher today than they were in 1980.
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