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An apartment complex installed a furnace 10 years ago at a cost of $23,000 to provide the necessary heating. Because of new additional, the existing unit will supply only 50% of the foretasted heating requirements. Currently, this old furnace has a salvage value of $9,000, and it is estimated that it can be used for additional 8-year period, with annual operating cost of $7,000, and a zero salvage value at the end of that time. If the old furnace is retained, a new unit with the same capacity will be purchased at a cost of $18,000. It is estimated that its service life, final salvage value, and operating cost are, respectively, 10 years, $3,000, and $6,000 per year. Another possibility is to buy a new furnace having the capacity of the two small units. This new unit has an initial cost of $32,000, estimated life of 12 years with $4,000 salvage value at the end of that time, and annual operating costs of $11,000. a) Define all the alternative that can be evaluated with the information given in the statement of the problem. b) if the MARR is 15% and using a study period of 8 year, which alternative should be selected? Use annual equivalent method