If a convex lens of focal length 80 cm and a concave lens of focal l – McqOptions

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1.	If a convex lens of focal length 80 cm and a concave lens of focal length 50 cm are combined together, what will be their resulting power [CBSE PMT 1996; AFMC 2002]
A.	+ 6.5D
B.	- 6.5 D
C.	+ 7.5 D
D.	- 0.75 D
Answer» E.

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