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A person is spinning with his hands outs...

A person is spinning with his hands outstretched at the rate of `3` rad/s.When he brings his hands close to the body,he spins at the rate of `9` rad/s.The ratio of initial rotational kinetic energy to final rotational kinetic energy of the person is

A

`1:2`

B

`1:3`

C

`2:3`

D

`1:9`

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