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Did you know?
The horizontal fraction bar was introduced by the Arabs.
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.
Did you know?
On average, the stomach produces 2 L of hydrochloric acid per day.
Did you know?
Parkinson's disease is both chronic and progressive. This means that it persists over a long period of time and that its symptoms grow worse over time.
Did you know?
Essential fatty acids have been shown to be effective against ulcers, asthma, dental cavities, and skin disorders such as acne.