a. What is the optimal number of years to operate the truck? Do not round intermediate calculations. Round your answers to the nearest whole number. years b. Would the introduction of salvage values, in addition to operating cash flows, ever reduce the expected NPV and/or IRR of a project? I. No. Salvage possibilities could only raise NPV and IRR. II. Yes. Salvage possibilities could only lower NPV and IRR. III. Salvage possibilities would have no effect on NPV and IRR