The Minute Maid Company (MMC) provides maids for house cleaning. Mr. Clean, the CEO of MMC estimates that the minimum numbers of maids required for the next year are: After hiring maids, Mr. Clean first sends them on a four-month training course. Following training, the maids begin active cleaning. Each month, 15% of the maids quit. Mr. Clean wants to determine the least number of new trainees to hire for the next eight months, while still maintaining the minimum requirements as indicated in the above table. At the beginning of January, the cleaning staff consists of 75 maids and 50 trainees. Half the trainees will begin active cleaning on 1st March and the rest will start on 1st April. We want to build an integer programming model and then use Excel's Solver to solve Mr. Clean's problem. The solution method used in Excel's Solver is a. GRG Nonlinear b. ROUNDUP c. Simplex LP d. Evolutionary