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If A=2pir, then r=...

If `A=2pir`, then r=_______

A

`2piA`

B

`(2pi)/(A)`

C

`(2A)/(pi)`

D

`(A)/(2pi)`

Text Solution

Verified by Experts

The correct Answer is:
D
`A=2pir` (Dividing both the sides with `2pi`).
`(A)/(2pi)=(2pir)/(2pi)rArrr=(A)/(2pi)`
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