Mr. Olivander has a monopoly on supplying magic wands. The table below shows the demand schedule for magic wands per day Quantity Price Demanded $100 0 $90 $65 2 $55 3 $35 $20 $15 12 Refer to the scenario above. What is Mr. Olivander's marginal revenue when he sells the third wand? a) $55. b) $35. c) $30. d) $130.