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Two thin lenses power +15 D and -5 D are...

Two thin lenses power `+15 D and -5 D` are cobined together. Their equilavlent focal length is

A

10 cm

B

`12.5` cm

C

`16.6` cm

D

`8.33 cm`

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The correct Answer is:
A
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TARGET PUBLICATION-RAY OPTICS-EVALUATION TEST
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