For the cash flows shown, determine: (a) the number of possible i* values (b) the i" value displayed by the IRR function (c) the external rate of retum using the MIRR method if I = 18% per year and I = 10% per year. Year Revenue, 5 Cost, $ 3 4,000 28,000 25,000 -30,000 19,000 --7,000 -6,000 -6,000 - 12,000