3) Consider the following investment: First cost -$1 million Year 1 $1 million Year 2 $1 million Year 3 $1 million Year 4 $1 million Year 5 -$1.5 million (a) Use the sign-change test to determine whether there could be multiple rates of return. (b) Determine all rates of return between 0% and 100% (e.g., by plotting the present worth of the investment as a function of the interest rate). Would this investment be desirable if your minimum acceptable rate of return is 20%? (c) Now change the payment in year 5 to-$5.5 million, and determine all rates of return. Explain why your answer is so different