200 (a) Profit Maximization $/q P* 100 0 2 -150 MC AC F E d 9=Q 6 8 10 MR (b) Total Cost, Revenue, and Profit $ At maximum-profit 600 point, slopes of TC and TR are parallel 400 $230 200 -200 2 $230 TC -Total cost -Total revenue At maximum-profit point, slope is zero and horizontal TR q=Q 6 8 10 TP -Total profit