Question

the spectacle containing which lens should be used by a person who can not see both the near and the distant object clearly?​

Answer 1

$\huge\mathfrak{Answer:-}$

⭕ First of all this Eye Defect is known as Presbyopia.It is caused in old age because of weakening of ciliary muscles.✔️

⭕ In this defect person is unable to see distant as well as Nearby objects clearly.

⭕ This defect is corrected by using bifocal lens of appropriate focal length.❤️

⭕ The upper part of lens is concave to correct Myopia. And the lower part of lens is Convex to correct Hypermetropia.

$\huge\mathfrak{Thank You :)}$