Two lenses of power +12 and - 2 diopters are placed in contact. What w – McqOptions

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1.	Two lenses of power +12 and - 2 diopters are placed in contact. What will the focal length of combination [MP PET 1990; MNR 1987; MH CET (Med.) 2001; UPSEAT 2000; Pb. PMT 2003]
A.	10 cm
B.	12.5 cm
C.	16.6 cm
D.	8.33 cm
Answer» B. 12.5 cm

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