2,800 2.400 2,000 TR 1.600 1.200 TC 800 400 TFC = 300 0 1 2 3 4 5 6 7 8 9 10 Pounds of carrots per month (thousands) 4. (Exhibit: Total Revenue, Total Costs, and Economic Profit) At zero level of output, total costs are and total revenue is a. 0; 0 b. 300; 0 c. 800; 300 d. 0; 300