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If the radius of a circle be increasing ...

If the radius of a circle be increasing at a uniform rate of `2cms^(-1)`. The rate of increasing of area of circle, at the instant when the radius is 20 cm is

A

`70picm^2//sec`

B

`70cm^2//sec`

C

`80picm^2//sec`

D

`80cm^2//sec`

Text Solution

Verified by Experts

The correct Answer is:
C
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