Question: A middle aged man starts to wear eyeglasses with lenses of
A middle-aged man starts to wear eyeglasses with lenses of +2.0 D that allow him to read a book held as close as 25 cm. Several years later, he finds that he must hold a book no closer than 33 cm to read it clearly with the same glasses, so he gets new glasses. What is the power of the new lenses?
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