1. Calculate the present value of each cash flow using a discount rate of 7%. Which do you most prefer most? Show and explain all supporting calculations! Cash flow A: receive $60 today and then receive $60 in four years. Cash flow B: receive $12 every year, forever, starting today. Cash flow C: pay $50 every year for five years, with the first payment being next year, and then subsequently receive $30 every year for 20 years. Cash flow D: receive $9 every other year, forever, with the first payment being next year