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Did you know?

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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Excessive alcohol use costs the country approximately $235 billion every year.

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The immune system needs 9.5 hours of sleep in total darkness to recharge completely.

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About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.

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Most women experience menopause in their 50s. However, in 1994, an Italian woman gave birth to a baby boy when she was 61 years old.

To cleanse an open wound, begin close to the wound and work outward in full or half circles. To cleanse an open wound, begin close to the wound and work outward in full or half circles.
When does old age begin? And what activities are appropriate for the elderly? From this photo that I ... When does old age begin? And what activities are appropriate for the elderly? From this photo that I ...
Gently squeeze the tissues along the eyebrow line between your thumb and forefinger. Begin at the ... Gently squeeze the tissues along the eyebrow line between your thumb and forefinger. Begin at the ...
Compound Angle Formulas Compound Angle Formulas
Binomial Formulas Binomial Formulas
chemical-nomenclature-and-chemical-formulas chemical-nomenclature-and-chemical-formulas
Video: The pH scale - Strong acids and Weak acids

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