A competitive firm has been selling its output for $10 per unit and has been maximizing its profit. Then, the price rises to $14, and the firm makes whatever adjustments are necessary to maximize its profit at the now-higher price. Once the firm has adjusted, its
a. marginal revenue is lower than it was previously.
b. marginal cost is lower than it was previously.
c. quantity of output is higher than it was previously
d. All of the above are correct.

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