A machinist turns the power on to a grinding wheel, at rest, at time t = 0 s. The wheel accelerates uniformly for 10 s and reaches the operating angular velocity of 21 rad/s. The wheel is run at that angular velocity for 39 s and then power is shut off. The wheel slows down uniformly at 2.2 rad/s2 until the wheel stops.

In this situation, the time interval of deceleration is closest to:

A) 14 s

B) 16 s

C) 10 s

D) 8 s

E) 12 s