Give meaning of the following : 

Range of vision

When Sahil tried to read a book by keeping it at a distance of $25 \mathrm{cm}$, the text print appeared to be blurred. What conclusion can be drawn about the 'least distance of distinct vision' of Sahil's eye?

A person, with a myopic eye, can not see objects beyond $1.2 \mathrm{m}$ distinctly. What can be said about the likely size of his eyeball? State the nature of the corrective lens that is needed to restore his proper vision?

Explain the function of the following part of the human eye.

Cornea