1. Economic rent The following graph shows a competitive labor market. ? 50 O 40 Labor Demand Labor Supply 30 Labor Supply WAGE RATE (Dollars per hour) 20 Economic Rent Labor Demand 10 Opportunity Cost 8 12 16 20 QUANTITY OF LABOR (Billions of hours) Based on the graph, the total amount paid to workers in this market (that is, total labor earnings) is On the graph, use the green triangle (triangle symbols) to shade the portion of labor earnings that consists of economic rent. Then, use the purple quadrilateral (diamond symbols) to shade the portion of labor earnings that consists of opportunity cost