Three mutual y exclusive design alternatives are being considered. The estimated cash flows for each alternative are given below. The MARR is 8% per year. At the end of the useful lde, the investment will be sold. A decision-maker can select one of these altenatives or decide to select none of them. Make a recommendation using the PW method. Investment cost Annual revenue Annual cost Useful Ife IRR PW $275,000 $140,000 $370,000 $76,130 $44.147 $76,470 $22,137 $10,188 $14,299 15 years 15 years 15 years 14.6% S399.913 $284.488 $407,138 18.0% 23.2% (a) Which alternative is the most economical? Choose the correct answer below O A. Alternative B O B. Alternative A C. None of the alternatives O D. Alternative C (b) Calculate the discounted payback period of each alternative. The discounted payback period of alternatve A is years. (Round to the nearest decimal. The discounted payback period of alternative Bisyears. (Round to the nearest decimal.) The discounted payback period of alternative C is years. (Round to the nearest decimal.) Based on the payback period, which altemative is the most preferred? Choose the correct answer below. O A. None of the alternatives O B. Alternative A O C. Alternative C O D. Alternative B (c) Why could the answers in (a) and (b) be different? O A. because the payback period gives more weight to the cash flows after the payback period O B. because the payback period method ignores the cash flows after the payback period