The angular acceleration of a wheel is ? = 5.0t4 – 3.0t2, with ? in radians per second-squared and t in seconds. At time t = 0, the wheel has an angular velocity of +7.0 rad/s and an angular position of +4.0 rad. Write expressions for (a) the angular velocity (rad/s) and (b) the angular position (rad) as functions of time (s).