Martin Company uses Miller-Orr model to manage its cash, using a money-market fund and a checking account. Martin keeps a minimum balance of $5000 in the checking account. The checking account pays no interest, but the money market pays 5% interest per annum. Martin has found the standard deviation of the cash flows to be $5120 per week. The cost of transferring the funds between the accounts is $125 per transfer. Assume that a year has 52 weeks. Find the following:

(A) The average checking account balance.

(B) The interest forgone in a year.