A design engineer must select the horsepower for a motor to drive a pump. Horsepower rating is a continuous design parameter with values in the range of 10 to 40 horsepower. The motor will have an annual ownership cost of $120 plus $0.60 per horsepower. The operating costs of such motors for 1 horsepower-hour will be $0.055 divided by the horsepower rating. Nine thousand horsepower-hours will be needed per year. (2.3) Determine what horsepower should be specified for a minimum total annual cost. Show that you have minimized total cost per year. (Sullivan, 20180327, p. 56) Sullivan, W. G., Wicks, E. M., Koelling, C. P. (20180327). Engineering Economy, 17th Edition [VitalSource Bookshelf version]. Retrieved from vbk://9780134838229 Always check citation for accuracy before use.