Please only answer if you can do all parts!

2. [20pts] Metro Telcom Systems develops, sells, and install computer systems. The company has divided its customer base into five regions, and it has 15 representatives who sell and install the company's systems. With its daily expense budget of $6,000, the company wants to allocate salespeople to regions so that they maximize daily sales revenue. However, whereas the sales increase as the number of salespeople allocated to a region increases, they do so at a declining rate, according to the nonlinear formula as Total sales = ai bi where t; is the number of salespersons allocated to region i for i = A, B, C, D, E. Following are the parameters a, and by for daily sales in each region and the daily expense (including all costs) per representative for each region: A 12,000 8,000 a, (S) Region i 20,000 12.000 B 16,000 10,000 D 18,000 14,000 E 16,000 16,000 Parameter b($) Daily expense for each region ($) 340 450 490 520 480 (a) Formulate a nonlinear programming model for this problem with integer decision variables. (b) Find the maximal daily sales and the optimal solution point in (a) by using the computer. (c) How much more sales can be produced if two more representatives were hired and the daily expense budget increased to $6,400? (d) What are the optimal objective value and solution point if Region A were disregarded from the original