An old person is unable to see clearly nearby objects as well as distant objects. $(i)$ What defect of vision is he suffering from? $(ii)$ What kind of lens will be required to see clearly the nearby as well as distant objects? Give reasons.

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(N/A) $(i)$ The person is suffering from $Presbyopia$.
$(ii)$ The person will require $Bifocal$ lenses. $Bifocal$ lenses consist of both convex and concave lenses. The upper portion consists of a concave lens to correct myopia (nearsightedness) for distant vision,and the lower portion consists of a convex lens to correct hypermetropia (farsightedness) for near vision. This combination allows the person to see both distant and nearby objects clearly.

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