Two small chemical feed pumps are under consid- eration for pumping a corrosive liquid from a 8.15 8.16 8.17 catalytic reforming process in a refinery. A pump with a brass impeller costs $800 and is expected to last 3 years. A pump with a stainless-steel impeller will cost $1900 and last 5 years. An overhaul cost- ing $300 will be required after 2000 operating hours for the brass impeller pump, while an over- haul costing $700 will be required for the stainless- steel pump after 9000 hours. If the operating cost of each pump is $0.50 per hour, how many hours per year must the pump be operated to justify the purchase of the more expensive pump at an inter- est rate of 10% per year? Solve using (a) factors, and (b) the PMT spreadsheet function and GOAL SEEK tool.