Suppose that the city of Portland Sanitation Department wants to improve their current capabilities of the solid-waste collection and disposal system, the Dempster Dumpmaster. They have 3 different alternatives that they are considering. The table below represents the initial cost (in year 0 ), annual operating costs, and annual savings for the three alternatives (in thousands of \$): The city plans to use the waste disposal system for another 20 years, with negligible salvage value. Suppose that the annual 0&M costs are expected to increase by 10% every year, and the interest rate is 8%. Answer the following questions: b. Calculate benefit-cost ratio for each alternative. Which alternative has the highest benefitcost ratio? Can we eliminate any of the given alternatives? c. Select the best alternatives using incremental benefit-cost analysis. Do you pick the alternative with the highest benefit-cost ratio (which you find in b.)