A financial institution estimates that it incurs the following costs and expenses each year on its demand deposits: Administration fee per account =$140; Average account balance =$1500, average checks cleared per account = 75 per month, cost of clearing a check=$0.1, and fees charged to customers = $0.05 per check, average monthly fees charged to customers =$8.

  (1). What is the interest cost for a financial institution to invest in a demand deposit?

（2）. If the bank reduced the minimum balance to $400, what would be the average return?

（3）.How much should a bank increase its cheque settlement fees to ensure that it pays an average interest rate of 5 per cent on this type of account, assuming that the minimum balance required is $750?