X-treme vitamin company is considering two investments, both of which cost $28,000. the cash flows are as follows: year project a project b 1 $ 30,000 $ 28,000 2 15,000 16,000 3 10,000 20,000 use appendix b for an approximate answer but calculate your final answer using the formula and financial calculator methods. a-1. calculate the payback period for project a and project b. (round your answers to 2 decimal places.)a-2. which of the two projects should be chosen based on the payback method? b-1. calculate the net present value for project a and project b. assume a cost of capital of 8 percent. (do not round intermediate calculations and round your final answers to 2 decimal places.)b-2. which of the two projects should be chosen based on the net present value method? c. should a firm normally have more confidence in the payback method or the net present value method?