a 1.50 kg book is sliding along a rough horizontal surface. at point a it is moving at 3.21 m/s, and at point b it has slowed to 1.25 m/s.

When amy exercises in her fitness center for 1 hr she burns a total of 475 calories.if she burns 9 calories a minute jogging on the treadmill and then burns 6.5 calories a minute pedaling on the stationary bicycle how many minutes of the hour does she spend exercising on the bicycle?