Marcus invested $5000 in a bank at an interest rate of 2.5% compounded annually. (a) Find the total amount he had at the end of second year. At the end of second year, Marcus withdrew all the money in the bank and invested it into another bank which offered simple interest rate of 8% per annum. (b) Find the minimum number of years he had to leave the money in the bank in order for it to be more than $10 000.​