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An astronomical telescope of magnifying ...

An astronomical telescope of magnifying power `8` is made using two lenses spaced `45cm` apart.The focal length of the lenses used are

A

`F= 40 cm , f= 5 cm `

B

`F = 8 cm , f= 5 cm `

C

`f= 5 cm , f= 47 cm `

D

`F= 20 cm , f=5 cm `

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The correct Answer is:
A
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