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?
According to the National Institute of Environmental Health Sciences, lung disease is the third leading killer in the United States, responsible for one in seven deaths. It is the leading cause of death among infants under the age of one year.
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Tobacco depletes the body of vitamins A, C, and E, which can result in any of the following: dry hair, dry skin, dry eyes, poor growth, night blindness, abscesses, insomnia, fatigue, reproductive system problems, sinusitis, pneumonia, frequent respiratory problems, skin disorders, weight loss, rickets, osteomalacia, nervousness, muscle spasms, leg cramps, extremity numbness, bone malformations, decayed teeth, difficulty in walking, irritability, restlessness, profuse sweating, increased uric acid (gout), joint damage, damaged red blood cells, destruction of nerves, infertility, miscarriage, and many types of cancer.
Prevalence of Obesity in the United States
The United States in the Caribbean and Central America
Population Projections of the United States
Examples of Muds and Clays from the United States and Around the World
The three states of matter: solid, liquid, and gas.
Approximately 40 percent of farmers in the United States are 55 years old or older