[填空题]
A centrifuge rotor rotatingc:.; vfh -/bwyyc,0: jtr).qi xmgvrc at 8u05ttgnwv b;wgo *5k: qki y3r4up z,10,300 rpm is shut off and is eventually brought uniformly to rest by a f:v,ku yut 5tng4iwkgz03qb;wr 8 *o p5rictional torque of 1.2 $m \cdot N$ If the mass of the rotor is 4.80 kg and it can be approximated as a solid cylinder of radius 0.0710 m, through how many revolutions will the rotor turn before coming to rest, $rev$ how long will it take? s