Question

Rewrite the following table so as to match the second and third column with the first column :

	Column I	Column II	Column III
1	Myopia	Old age problem	Bifocal lens
2	Presbyopia	Near-sightedness	Concave lens

Answer 1

Myopia $\to$ Near-sightedness $\to$ Concave lens
Presbyopia $\to$ Old age problem $\to$ Bifocal lens

Myopia is the defect of the human eye in which nearby objects are seen clearly but far away objects are not seen distinctly. This defect can be corrected by using a concave lens, this will diverge the rays such that the eye lens focuses it on the retina.

In Presbyopia the power of accommodation of the eye usually decreases with age. The near point gradually recedes away. Old people find it difficult to see nearby objects comfortably and distinctly without corrective eyeglasses. Such people often require bifocal lenses. A common type of bifocal lenses consists of both concave and convex lenses.