please ansewer A and B with work.

5. An additional unit of Old Product X will bring Cindy an MU of 30 utils; an additional unit of New Product Y will bring Cindy an MU of 40 utils; and an additional unit of New Product Z will bring Cindy an MU of 50 utils. If a unit of Old Product X costs $10, a until of New Product Y costs $30, and a unit of New Product Z costs $20, (A) which product will Cindy prefer to spend her money on? (B) Show your work for each product. a. Old Product X. b. New Product Y. c. New Product Z. d. More information is required