The cost of a new subsystem for a power plant will cost $80,000. The annual operation and maintenance costs and market values are as follows: O&M expense = $30,000 (EOY1) $30,000 (EOY2) $35,000 (EOY3) $40,000 (EOY4) $45,000 (EOY5) MV = $60,000 (EOY1) $50,000 (EOY2) $40,000 (EOY3) $25,000 (EOY4) $12,500 (EOY5) Determine the best time to replace the subsystem if the MARR is 15% per year.