If firms can easily enter and exit a market, then a. firms will produce at minimum average cost in the short run. b. firms will produce where price is less than marginal cost. c. firms will earn zero economic profit in the long run. d. firms will produce where price is greater than marginal revenue. e. firms will produce at minimum average fixed cost in the long run.

Assume that a local bank sells two services, checking accounts and atm card services. the bank’s only two customers are mr. donethat and ms. beenthere. mr. donethat is willing to pay $8 a month for the bank to service his checking account and $2 a month for unlimited use of his atm card. ms. beenthere is willing to pay only $5 for a checking account, but is willing to pay $9 for unlimited use of her atm card. assume that the bank can provide each of these services at zero marginal cost. refer to scenario 17-5. if the bank is unable to use tying, what is the profit-maximizing price to charge for a checking account