More than 4.2 million Americans aged 40 years and older are either legally blind (having best-corrected visual acuity of 6/60 or worse (=20/200) in the better-seeing eye) or are with low vision (having best-corrected visual acuity less than 6/12 (<20/40) in the better-seeing eye, excluding those who were categorized as being blind).
The leading causes of blindness and low vision in the United States are primarily age-related eye diseases such as age-related macular degeneration, cataract, diabetic retinopathy, and glaucoma. Other common eye disorders include amblyopia and strabismus.
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Refractive Errors
Refractive Errors
Refractive errors are the most frequent eye problems in the United States. Refractive errors include myopia (near-sightedness), hyperopia (farsightedness), astigmatism (distorted vision at all distances), and presbyopia that occurs between age 40–50 years (loss of the ability to focus up close, inability to read letters of the phone book, need to hold newspaper farther away to see clearly) can be corrected by eyeglasses, contact lenses, or in some cases surgery. The National Eye Institute states that proper refractive correction could improve vision among 150 million Americans.
Answer:
it's a watershed
Explanation:
basically it's a channel that drains/carries runoff to a common point like the lake in the picture. water, sediment, and other materials are carried by the river to the lake.
Explain why some lobsters may have one claw that is larger than the other claw. ... Why might it be particularly beneficial for the giant spider crab to be so large<span>?</span>
Answer:
Psychasthenia is a neurotic state characterized especially by phobias, obsessions, or compulsions that one knows are irrational.
D. I think but I’m not 100% on that