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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The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
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There are 20 feet of blood vessels in each square inch of human skin.
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Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%
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The first oncogene was discovered in 1970 and was termed SRC (pronounced "SARK").
Which do you think is most at work in a debate contest, mastery- or performance-goal orientations or ...
