Costs 0 40 70 80 90 MC ATC AVC AFC Quantity Refer to the graph above to answer this question. At what output is marginal product at the maximum point? 40. 70. 80. 90.

Refer to the graph above to answer this question. Aplwhat output is marginal product at the maximum point? \begin{tabular}{r} 40 \\ 70 \\ \hline 80 \\ \hline 90 \\ \hline \end{tabular}