Your best friend Sam is in discussion with you about saving for his retirement. You are to advise him on how much he should deposit annually to meet his retirement needs. Assume that he will deposit a fixed annual amount for the next 20 years into a retirement savings account, starting one year from now. Sam has a son who will be attending college and plans to make 5 withdrawals (starting one year after making his final deposit into the retirement account) of $35,000 each to pay for his annual tuition for the following 5 years. Commercial Banks will be paying 6 percent on such retirement accounts for the next 25 years. Kindly advise Sam on how much he should place in the account annually to cover his retirement needs.