A manufacturing company is willing to buy a milling machine for its new plant. The aim of the company is to maximize the profit, minimize the mean time between failures of the machine, and maximize the service quality. Service quality includes the quality of education given by the service staff to the employers of the company and the duration of repairing time in case of a break-down. There are three milling machine brands, namely, FESTO, ABB and Siemens which offers milling machines for the same cost. The company has to choose one of these three brands. The following table gives the result of expert evaluations about the brands. (Hint: Average profit/day = Average number of units milled / day* Average profit / milled unitFixed cost/ day) a) Determine the critical variables for daily profit if any. b) Assume that education quality and duration of repairing time have the same importance to the company; while profit is twice as important as service quality and three times as important as mean time between failures. Which brand should the company choose? c) Now assume that repairing time duration is twice as important as education quality while profit, mean time between failures and service quality have the same importance. Which brand should the company choose