Harry owns a snow-removal business. He hires workers to shovel driveways for him during the winter. The first worker he hires can shovel twelve driveways in one day. When Harry hires two workers, they can shovel a total of 22 driveways in one day. When Harry hires a third worker, he shovels an additional eight driveways in one day. Suppose that Harry pays each worker $80 per day and that he charges each customer $20 to have his driveway shoveled. What is the value of the marginal product of labor for the second worker

Why is the cournot equilibrium an​ equilibrium? a. there are​ short-run barriers to exit in a cournot​ duopoly, so both firms cannot alter their output levels. b. given the other​ firm's level of​ production, both firms are maximizing profits and cannot improve their situation by unilaterally altering their level of output. c. both firms operate at zero profit under a cournot​ equilibrium, so they would face negative profits if they change output. d. both firms operate at minimum​ long-run average cost under a cournot​ equilibrium, so changes to output would reduce​ long-run profits. even if they​ can't collude, why​ don't firms set their outputs at the joint​ profit-maximizing levels​ (i. e., the levels they would have chosen had they​ colluded)? a. given that other firm produces at the collusive​ level, a firm could increase their own profits by increasing output above the collusive level. b. the midpoint of the collusion curve​ (i. e., the collusive​ outcome) lies below the reaction​ curves, so both firms have an incentive to increase output under the cournot duopoly. c. both a and b are correct d. both a and b are incorrect