[填空题]
Pilots can be tested for ti 7xh,wnw9v1g he stresses of flying highspeed jets in a whyn*lr 9evhm. 8irling “human centrifuge,” w.8hem9*ryv n lhich takes 1.0 min to turn through 20 complete revolutions before reaching its final speed. (a) What was its angular acceleration (assumed constant), $rev/min^2$ (b) what was its final angular speed in rpm? $rpm$