Refer to Figure 17.2.3. The graph provides information about a waste disposal system in a city of 1 million people. If the city installs the efficient capacity, then each person pays in taxes. Marginal cost and marginal benefit (dollars per person) 115 105 95 85 75 65 55 45 35 25 15 1 2 3 MSC MSB 4 5 Capacity (millions of litres per day) Figure 17.2.3