Suppose your firm is evaluating four potential new investments. You calculate that these projects, W, X, Y, and Z, have the NPV and IRR figures given below: Project W: NPV -$1000 IRR = 20% Project X: Project Y: Project Z: NPV = $3,000 IRR = 15% NPV = -$800 NPV = $2,000 IRR = 9% IRR=18% a) Which project(s) should be accepted if they are independent? Clearly explain your reasoning. b) Which project(s) should be accepted if they are mutually exclusive? Clearly explain your reasoning.