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When a telescope is adjusted for paralle...

When a telescope is adjusted for parallel light, the distance of the objective from the eye piece is found to be `80 cm`. The magnifying power of the telescope is 19 . The focal length of the lenses are

A

61 cm, 19 cm

B

40 cm, 40 cm

C

76 cm, 4 cm

D

50 cm, 30 cm

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The correct Answer is:
C
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