Yvonne has gained a reputation for her cheesecakes. She takes orders for 10 cheesecakes and spends 8.5 hours on one Saturday baking them all. She earns $120 from selling these cheesecakes. a. What is the average length of time to make one cheesecake? Give your answer in minutes. b. What does Yvonne charge for each cheesecake? c. How much money is Yvonnne earning per hour for her work?