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4. A record turntable rotates at 45 rpm. At t = 0 s, the power to the turntable is shut off and the turntable slows at a constant angular acceleration. The turntable comes to rest after 20 s. What was the angular acceleration of the turntable as it was slowing down? A) 0.096 rad/s2 B) 0.24 rad/s2 C) 0.12 rad/s2 D) 0.038 rad/s2 E) 0.062 rad/s2 5. A space vehicle is traveling at 4500 km/h relative to the Earth when the exhausted rocket motor is disengaged and sent backward with a speed of 90.0 km/h relative to the command module after separation. The mass of the motor is exactly four times the mass of the module. What is the speed of the command module relative to Earth after the separation? A) 22,900 km/h B) 4,570 km/h C) 4,780 km/h D) 4,430 km/h