Two disks are mounted (like a merry-go-round) on low-friction bearings on the same axle and can be brought together so that they couple and rotate as one unit. The first disk, by rotational inertia 4.31 kg·m2 about its central axis, is set spinning counter clockwise (which might be taken as the positive direction) at 125 rev/min. The second disk, with rotational inertia7.93 kg·m2 about its central axis, is set spinning counter clockwise at 907 rev/min. They then couple together. (a) What is their angular speed (rev/min) after coupling? (b) If instead the second disk is set spinning clockwise at 907 rev/min, what is their angular velocity (in rev/min, using the correct sign for direction) after they couple together?