If Sam, the Pizza Man, lowers the price of his pizzas from $6 to $5 and finds that sales increase from 400 to 600 pizzas per week, then the demand for Sam's pizzas in this range is: A) price elastic. B) income inelastic. C) cross elastic. D) price inelastic. E) unit elastic. A local restaurant offers an "all you can eat" Sunday brunch for $12. Susan eats four servings, but leaves half of a fifth helping uneaten. Why? A) Her marginal value of a serving has fallen below $2.36 ($12 divided by 5 servings). B) The total value she places on brunch today exactly equals $12. C) Her marginal value of food has fallen to zero. D) Her marginal value of a serving of brunch has fallen below $12.