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A convex lens focal lenghts 30 cm made o...

A convex lens focal lenghts 30 cm made of glass of refractive index `1.5` is immersed in water having refrctive `1.33`. The change in the focal length of lens is

A

62.2 cm

B

87.4cm

C

58.2 cm

D

73.6 cm

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