Price Quantity Quantity Supplied Quantity Supplied Demanded without Paying after Paying Social Social Costs Costs 100 0 120 75 80 10 100 50 55 30 90 30 40 55 85 25 30 80 80 20 20 100 65 15 The equilibrium price and quantity when only private costs are taken into account are ( a) Price = $30, Quantity = 20 ( b) Price = $40, Quantity = 55 c) Price = $55, Quantity = 30 O d) Price = $30, Quantity = 80