Find the present values of these ordinary annuities. Discounting occurs once a year. Do not round intermediate calculations. Round your answers to the nearest cent. a. $300 per year for 12 years at 8%. $ b. $150 per year for 6 years at 4%. $ C. $1,000 per year for 6 years at 0%. $ d. Rework previous parts assuming they are annuities due. Present value of $300 per year for 12 years at 8%: $ Present value of $150 per year for 6 years at 4%: $ Present value of $1,000 per year for 6 years at 0%:$