420 OUTPUT (Units ) 210 120 LABOR (Number ofworkers) Refer to Figure 18-1. a. The marginal product of the second worker is 90 units of output. Note: the marginal product of labor is defined as the change in output per additional unit of labor. b. Suppose the firm hires each unit of labor for $600 per week, and each unit of output sells for $9. What is the value of the marginal product of the third worker? $675 C. Suppose the firm sells its output for $12 per unit, and it pays each of its workers $700 per week. How many workers will the firm hire to maximize 1 it? 4 Answer 1: 90 Answer 2: $675 Answer 3: 4