Bill is comparing offers from two banks on checking accounts that include debit cards. Bank A charges a $10 monthly fee for a checking account and debit card, plus 0.50 for each transaction. Bank B charges a $25 monthly fee for a checking account and debit card, with unlimited transactions. Suppose Bill makes 25 transactions in a given month. Answer the questions below. How much would he pay at each bank for the given month?
Bank A:

Bank B:
(b) For the given month, which bank is cheaper and by how much?

Bank A

Bank B