Calculate the present value of the following: a-1. Annual payment of $800 for 10 years at 5% interest. (Do not round intermediate calculations. Round your answer to 2 decimal places.) Present value a-2 Annual payment of $600 for 15 years at 5% interest. (Do not round intermediate calculations. Round your answer to 2 decimal places.) Present value a-3. Which option would you prefer? $800 a year for 10 years $600 a year for 15 years b-1. Annual payment of $800 for 10 years at 20% interest. (Do not round intermediate calculations. Round your answer to 2 decimal places.) Present value