Jane has the following utility function for jelly beans: U (I ) = 20] :12 with M U I = 20 j . a. Plot the utility and marginal utility functions on two separate graphs. (2 marks) b. Suppose that Jane is allowed to eat as many jelly beans as she likes and that jelly beans cost her nothing. Show, both algebraically and graphically, the value of J at which she would stop eating jelly beans. (2 marks)