Physics Rotational Mechanics Level: Misc Level

A machinist turns the power on to grinding wheel, at rest, at time t =0 s. The wheel accelerates uniformly for 10 s and reaches the operating angular velocity of 80 rad/s.The wheel is run at that angular velocity for 20 s and then power is shut off.The wheel decelerates uniformly at 1.3 rad/s2 until the wheel stops. In this situation, the angular acceleration of the wheel between t =0 s and t= 10 s is closest to :

A) 8.0 rad/s2 B) 14 rad/s2 C) 13 rad/s2 D) 9.6 rad/s2 E) 11 rad/s2