Rock Solid Bank and Trust (RSB&T) offers only checking accounts. Customers can write checks and use a network of automated teller machines. RSB&T earns revenue by investing the money deposited; currently, it averages 6.10 percent annually on its investments of those deposits. To compete with larger banks, RSB&T pays depositors 0.50 percent on all deposits. A recent study classified the bank's annual operating costs into four activities. Activity Using ATM Visiting branch Processing transaction Managing functions Total overhead Cost Driver Number of uses Cost $ 2,850,000 Driver Volume 3,800,000 uses Number of visits Number of transactions 1,710,000 12,540,000 Total deposits 285,000 visits 152,000,000 transactions 11,400,000 $712,500,000 in deposits $28,500,000 Data on two representative customers follow. Customer A Customer B ATM uses 100 200 Branch visits 5 Number of transactions 40 Average deposit $6,000 20 1,500 $6,000 Required: a. Compute RSB&T's operating profits. b. Compute the profit from Customer A and Customer B, assuming that customer costs are based only on deposits. Interest costs = 0.50 percent of deposits; operating costs are 4 percent (= $28,500,000/$712,500,000) of deposits. c. Compute the profit from Customer A and Customer B, assuming that customer costs are computed using the information in the activity-based costing analysis.