An average person burns off 100 calories if they bicycle for 15 minutes at 9 mph. There are approximately 3,500 calories in one pound. Harry signed up at the local fitness center and spent 45 minutes on the stationary bicycle pedaling at a steady rate of 9 mph. How many calories did he burn? Did he use up a pound? Select one: a. 4,500 calories; yes b. 300 calories; no c. 3,200 calories; no d. 900 calories; no