The tub of a washer goes into its spin dry cycle, starting from rest and reaching an angular speed of 5.0 rev/s in 8.0 s. At third point, the person doing the laundry opens the lid, and a safety switch turns off the washer. The tub slows to rest in 12.0 s. Through how many revolutions does the tub turn during the entire 20 s interval? Assume constant angular acceleration while it is starting and stopping.
