A far sighted person cannot see objects that are less tha...
A far sighted person cannot see objects that are less than 100cm away. If this person wants to read a book at 25cm, what type and focal length of lens does he need?
convex, 20cm
concave, 20cm
convex, 33cm
concave, 33cm
Correct answer is D
No explanation has been provided for this answer.
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