$115, C1 = -$120, C2 = -$80, 6. (Extra 12 points) Suppose that project's cash flows are Co C3 = -$40, C4 = $130. Required rate of return is 15%. (a) (4 points) Compute NPV. Should you take the project based on the NPV rule? (b) (4 points) Taking into account cash flow structure of this project, compute IRR of this project. (c) (4 points) What would be an appropriate IRR rule for this project (i.e., for which required rates of return the project should be accepted)