Which of the following statements related to the internal rate of return (IRR) are correct? I. The IRR method of analysis is useful for comparing mutually exclusive projects. II. The IRR that causes the net present value of the differences between two project's cash flows to equal zero is called the crossover rate. III. It is possible for there to be multiple IRRs. IV. Both the timing and the amount of a project's cash flows affect the value of the project's IRR.