National Bank operates a network of automated teller machines (ATM). Assume that there are 52 weeks per year. Cash withdrawals at an ATM average about $80. The bank estimates that the fixed cost of filling an ATM with cash is about $100 regardless of the amount of cash put in. Average numbers of cash withdrawals per week is about 150. To minimize the total cost, how much should the bank replenish an ATM each time if its annual cost of money is 10%?