Firms A and B compete a la Bertrand. The cost functions for firms A and B are T()=20 and T()=55 respectively. What are the cost functions for firms A and B?
a. TCA(qA)=20qA, TCB(qB)=55qB
b. TCA(qA)=55qA, TCB(qB)=20qB
c. TCA(qA)=qA/20, TCB(qB)=qB/55
d. TCA(qA)=qA/55, TCB(qB)=qB/20