how can i solve these while plugging them into the BAII plus calculator/excel

Problem 5-15 Present value of an annuity Find the present values of these ordinary annuities. Discounting occurs once a year. Round your answers to the nearest cent. a. $200 per year for 16 years at 16%. b. $100 per year for 8 years at 8%. C. $600 per year for 12 years at 0%. 7200 Rework previous parts assuming that they are annuities due. Round your answers to the nearest cent. d, $200 per year for 16 years at 16%. e, $100 per year for 8 years at 8%. f. $600 per year for 12 years at 0% 7200