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Lenses of +2 D, +3 D and -1.5 D are placed in contact. The total power is:
A3.5 D
B6.5 D
C2.5 D
D-3.5 D
Answer & Solution
Correct answer: A. 3.5 D
Powers of lenses in contact add, so 2 + 3 - 1.5 = 3.5 D.
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