Two concave lenses of 60 cm focal length are cemented on either side o – McqOptions

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1.	Two concave lenses of 60 cm focal length are cemented on either side of a convex lens of 15 cm focal length. The focal length of the combination is
A.	10 cm
B.	20 cm
C.	30 cm
D.	40 cm
Answer» D. 40 cm

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