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GECO is contracted for the next 4 years to supply aircraft engines at the rate of four engines a year. Available production capacity and production costs vary from year to GECO can produce five engines in year 1, six in year 2, three in year 3, and five year. in year 4. The corresponding production costs per engine over the next 4 years are $200,000, $330,000, $350,000, and $420,000, respectively. GECO can elect to produce more than it needs in a certain year, in which case the engines must be properly stored until shipment date. The storage cost per engine also varies from year to year, and is to be $20,000 for year 1, $30,000 for year 2, $40,000 for year 3, and $50,000 year 4. Currently, at the start of year 1, GECO has one engine ready for shipping. estimated for Develop an optimal production plan for GECO