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A candle placed 25 cm from a lens, forms...

A candle placed 25 cm from a lens, forms an image on a screen placed 75 cm on the other end of the lens. The focal length and type of the lens should be

A

`+18.75` cm and convex lens

B

`18.75` cm and concave lens

C

`+20.25` cm and convex

D

`-20.25` cm and concave lens

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The correct Answer is:
A
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