(Market 6) Use the graph to answer the question. Marginal Price private cost $18 $15 $12 $9 $6 $3 - Marginal- Marginal private benefit social benefit 2 4 6 8 10 12 Quantity The graph shows the marginal social benefit, marginal private benefit, and marginal private curves in the taco market. If market forces prevail, output will be and the price will be O 6; $9 O 4; $6 0 9;$6 O 6; $4