Light rays entering the eye are refracted by the lens and form an image on a specific part of the eye. What is this part called?

Sometimes you see a person reading the newspaper by placing it very close to his eyes. Which defect is he suffering from? How can the defect be removed?

State the function of the pupil and ciliary muscles.

Which of the following is true for the eye defect known as hypermetropia (farsightedness)?

$(a)$ State two main causes of a person developing near-sightedness. How can this defect be corrected?
$(b)$ What is 'astigmatism' and how is this vision defect corrected?

$A$ person needs a lens of power $-2.5 \ D$ for correcting his vision. Name the defect of vision he is suffering from. Which lens will he be using for the correction? Also,find the focal length of the lens.