A disk rotates about its central axis starting from rest and accelerates with constant angular acceleration. At one time it is rotating at 12 rev/s. 50 revolutions later, its angular speed is 16 rev/s. (a) Calculate the angular acceleration. rev/s2 (b) Calculate the time required to complete the 50 revolutions mentioned. s (c) Calculate the time required to attain the 12 rev/s angular speed. s (d) Calculate the number of revolutions from rest until the time the disk attained the 12 rev/s angular speed.