Doreen's Dairy produces and sells Swiss cheese. Last year, it produced 7,000 pounds and sold each pound for $6. In producing the 7,000 pounds, the dairy incurred variable costs of $28,000 and a total cost of $40,000.
The firm's fixed cost was
A. $2,000.
B. $28,000.
C. $12,000.
D. $42,000.