The table above shows Danielle's utility from ice cream and romance novels

.a) What is Danielle's marginal utility from the 4th novel?

b) The price of ice cream is $5 per gallon and a novel is $10. If Danielle's budget for these two goods is $50 and she buys 2 gallons of ice cream, how many novels can she buy? If she buys 6 gallons of ice cream, what is her marginal utility per dollar spent on novels?
c) Which combination of the two goods is better: 4 gallons of ice cream and 3 novels or 6 gallons of ice cream and 2 novels?

Ice cream Romance novels Quantity Total utility Quantity Total utility 1 95 1 170 180 2 320 3 255 3 450 4 320 4 560 5 375 5 650 6. 420 6. 720