Answer the question based on the following information for a public good.P_aandP_bare the prices that individuals A and B are willing to pay for the last unit of a public good, rather than do without it. These people are the only two members of society.

QP_aP_b1$ 3$ 5224313402501

If the marginal cost of producing this good at the optimal quantity is $8, the optimal quantity must be

Multiple Choice

• 5 units.
• 1 unit.
• 3 units.
• 4 units.
• 2 units.