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A child is standing with folded hands at...

A child is standing with folded hands at the center of a platform rotating about its central axis. The kinetic energy of the system is `K`. The child now stretches his arms so that the moment of inertia of the system doubles. The kinetic energy of the system now is

A

1, 2 and 3 are correct

B

1 and 2 are correct

C

2 and 4 are correct

D

1 and 3 are correc

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