Suppose Al, Betty, and Carl Own the Only Fishing Companies

Multiple Choice

Suppose Al, Betty, and Carl own the only fishing companies in your village. Suppose the market price today is $10 per fish. Suppose Al catches 4,000 fish with an average total cost of $7.50, Betty catches 6,000 fish with an average total cost of $6, and Carl catches10,000 fish with an average total cost of $5. If everyone is a profit maximizer, what is Betty's marginal cost?

A) $6
B) $7
C) $8
D) $9
E) $10