A wheel has a constant angular acceleration of 3.0 rad/s2, During a certain 4.0 s interval, it turns through an angle of 120 rad. Assuming that at t = 0, angular speed ω0 = 3 rad/s how long, is motion at the start of this 4.0 second interval ?
(1) 7 sec. (2) 9 sec. (3) 4 sec. (4) 10 sec.