Through which part of the eye do light rays from an object first enter the eye?

Sometimes you see a person reading the newspaper by placing it far away from their eyes. Which defect is the person suffering from? How can this defect be corrected?

$A$ person can see distant sign boards clearly but cannot read clearly a book which is at $25\, cm$ from his eye. Giving reason,identify the defect. Draw a labelled ray diagram to illustrate this defect and its correction.

What is the lens placed near the eye in a compound microscope called?

How can a change in the size of the eyeball be a reason for $(a)$ Myopia and $(b)$ Hypermetropia? Compare the size of the eyeball with that of a normal eye in each case. How does this change in size affect the position of the image in each case?

$(i)$ What is the least distance of distinct vision for a normal eye?
$(ii)$ Does the above distance increase or decrease for a long-sighted eye (hypermetropia)? Give a reason for your answer with a diagram.