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-21 All techniques, conflicting rankings Nicholson Roofing Materials Inc. is considering two mutually exclusive projects, each with an initial investment of $150,000. The company's board of directors has set a maximum 4-year payback requirement and has set its cost of capital at 9%. The cash inflows associated with the two projects are shown in the following table. Cash inflows (CF,) Year Project A Project B $45,000 $75,000 W N 45,000 60,000 45,000 30,000 45,000 30,000 45,000 30,000 45,000 30,000 a. Calculate the payback period for each project. b. Calculate the NPV of each project at 0%. c. Calculate the NPV of each project at 9%. d. Derive the IRR of each project. e. Rank the projects by each of the techniques used. Make and justify a recommendation. f. Go back one more time and calculate the NPV of each project using a cost of capital of 12%. Does the ranking of the two projects change compared to your answer in part e? Why