$A$ person is able to see objects clearly only when these are lying at distances between $50 \text{ cm}$ and $300 \text{ cm}$ from his eye. Identify the kind of defects of vision he is suffering from. Give reason for your answer.

(N/A) The person is suffering from both myopia (short-sightedness) and presbyopia.
$1$. The near point of a normal eye is $25 \text{ cm}$. Since the person's near point is $50 \text{ cm}$, he cannot see objects closer than $50 \text{ cm}$, which indicates presbyopia (or hypermetropia).
$2$. The far point of a normal eye is infinity $(\infty)$. Since the person's far point is limited to $300 \text{ cm}$, he cannot see distant objects clearly, which indicates myopia (short-sightedness).