Pls solve Q25. Also explain the answers..

i)
a)when the student is sitting in front desk, image is formed behind the retina.Therefore the student sees the image as blurred and unclear.

b)when the student is sitting  on the last desk,image is correctly focussed on the retina.So he sees the board clearly.

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ii) Now, this defect ca be corrected using a Convex Lens

iii)Here the student is unable to see nearby objects clearly but can see the distant objects clearly.So he is suffering from longsightedness/Hypermetropia. This can occur due to:

• Focal length of the eye lens become too long.
• Eyeball has become too small.