A certain firm produces and sells staplers. Last year, it produced 7,000 staplers and sold each stapler for $6. In producing the 7,000 staplers, it incurred variable costs of $28,000 and a total cost of $45,000.
In producing the 7,000 staplers, the firm's average fixed cost was
a. $2.21
b. $1.00
c. $2.43
d. $1.32