QUESTION
Feedback See Hint The table below shows the marginal private benefits and the marginal private costs of flu shots. The marginal private benefits represent the market demand curve $\left(\mathrm{D}_{\text {Int }}\right)$, and the marginal private costs represent the market supply curve $\left(\mathrm{S}_{\text {Int }}\right)$. \begin{tabular}{|c||c||c||} \hline \multicolumn{1}{|c||}{ Quantity of flu shots } & $\begin{array}{c}\text { Marginal private benefits } \\ \mathrm{D}_{\text {Internal }}\end{array}$ & $\begin{array}{c}\text { Marginal private costs } \\ \mathrm{S}_{\text {Internal }}\end{array}$ \\ \hline \hline 1,000 & $\$ 2,500$ & $\$ 1,800$ \\ \hline 2,000 & $\$ 2,250$ & $\$ 1,900$ \\ \hline 3,000 & $\$ 2,000$ & $\$ 2,000$ \\ \hline 4,000 & $\$ 1,750$ & $\$ 2,100$ \\ \hline 5,000 & $\$ 1,500$ & $\$ 2,200$ \\ \hline 6,000 & $\$ 1,250$ & $\$ 2,300$ \\ \hline 7,000 & $\$ 1,000$ & $\$ 2,400$ \\ \hline 8,000 & $\$ 750$ & $\$ 2,500$ \\ \hline 9,000 & $\$ 500$ & $\$ 2,600$ \\ \hline \hline \end{tabular} Suppose that getting a flu shot generates a positive externality, and the external benefit is $\$ 1,500$ per thousand flu shots. Compared to the socially optimal amount of flu shots, the amount of flu shots taken at the market equilibrium is 3000 shots too