Suppose that a (very) small neighborhood has five people who would like to take the bus. However, no single individual is willing to pay the entire cost of the bus. Given the marginal benefits of bus trips below, and assuming the marginal cost of an additional bus trip is $20, how many trips would be optimal? Person 1's Person 2's Person 3's Person 4's Person 5's Marginal Marginal Marginal Marginal Marginal Number of Bus Trips