Question

The tub of a washer goes into its spin cycle, starting from rest and gaining angular speed steadily for 9.58 s, at which time it is turning at 3.89 rev/s. At this point, the person doing the laundry opens the lid, and a safety switch turns off the washer. The tub smoothly slows to rest in 13.0 s. Through how many revolutions does the tub turn while it is in motion?



I have no idea how to solve this problem can someone help me please? Thank you very much