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Consider the following cash flow profile and assume MARR is 10%/yr. EOY NCF EOY NCF 0 -$100 4 $250 1 $25 5 -$200 2 $200 6 -$100 3 -$100 a. What does Descartes' rule of signs tell us about the IRR(s) of this project? b. What does Norstrom's criterion tell us about the IRR(s) of this project? c. Determine the IRR(s) for this project. d. Is this project economically attractive