A special-purpose 30-horsepower electric motor has an efficiency of 90%. Its purchase and installation price is $2,100. A second 30-horsepower high-efficiency motor can be purchased for $3,200, and its efficiency is 92%. Either motor will be operated 4,500 hours per year at full load, and electricity costs $0.10 per kilowatt-hour (kWh). MARR =15% per year, and neither motor will have a market value at the end of the eight-year study period. a. Which motor should be chosen? b. For an incremental investment of $1,100 in the more efficient motor, what is the PW of the energy savings over the eight-year period? Recall that 1hp=0.746kW. Click the icon to view the interest and annuity table for discrete compounding when i=15% per year. a. The PW of the motor with the efficiency of 90% is $. (Round to the nearest dollar.) Discrete Compounding; i=15% A special-purpose 30-horsepower electric motor has an efficiency of 90%. Its purchase and installation price is $2,100. A second 30-horsepower high-efficiency motor can be purchased for $3,200, and its efficiency is 92%. Either motor will be operated 4,500 hours per year at full load, and electricity costs $0.10 per kilowatt-hour (kWh). MARR =15% per year, and neither motor will have a market value at the end of the eight-year study period. a. Which motor should be chosen? b. For an incremental investment of $1,100 in the more efficient motor, what is the PW of the energy savings over the eight-year period? Recall that 1hp=0.746kW. Click the icon to view the interest and annuity table for discrete compounding when i=15% per year. a. The PW of the motor with the efficiency of 90% is $. (Round to the nearest dollar.) Discrete Compounding; i=15%