Did you know?

The average office desk has 400 times more bacteria on it than a toilet.

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There are 20 feet of blood vessels in each square inch of human skin.

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Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.

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The highest suicide rate in the United States is among people ages 65 years and older. Almost 15% of people in this age group commit suicide every year.

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Astigmatism is the most common vision problem. It may accompany nearsightedness or farsightedness. It is usually caused by an irregularly shaped cornea, but sometimes it is the result of an irregularly shaped lens. Either type can be corrected by eyeglasses, contact lenses, or refractive surgery.

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