Suppose That for a Particular Firm the Only Variable Input

Multiple Choice

Suppose that for a particular firm the only variable input into the production process is labor and that output equals zero when no workers are hired. In addition, suppose that when the firm hires 2 workers, the total cost of production is $100. When the firm hires 3 workers, the total cost of production is $120. In addition, assume that the variable cost per unit of labor is the same regardless of the number of units of labor that are hired. What is the firm's fixed cost?

A) $40
B) $60
C) $80
D) $100