A manufacturing firm is the sole seller of a specialized machine. The demand schedule for this product is shown in the table below. Price $700 000 $600 000 $500 000 $400 000 $300 000 $200 000 $100 000 Quantity Demanded 0 2 4 5 6 4. For this firm, the marginal revenue of the third machine is: A) $600 000 B) $400 000 C) $200 000 D) $0 E) -$200 000