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The length of a telescope is 36 cm . The...

The length of a telescope is 36 cm . The focal lengths of its lenses can be

A

`30cm , 6 cm`

B

`-30 cm , -6 cm`

C

`30 cm , -6 cm`

D

`-30 cm , 6 cm`

Text Solution

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The correct Answer is:
a
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ERRORLESS -RAY OPTICS-SET
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