DJB Electronics produces three types of satellite dish; Alpha, Beta and Gamma. The contributions per unit from these products are 400, 200 and 100 respectively. Manufacture involves a two-stage process and the number of hours per unit required at each stage are: Alpha Beta Gamma Stage 1 2 3 2.5 Stage 2 3 2 2 There is an upper limit on process hours of 1,920 hours per month for Stage 1 and 2,200 hours per month for Stage 2. The Alpha dish was designed to receive from a low-power satellite, which is now fading, and the sales manager of DJB thinks that sales will be no more than 200 per month. There are no limits at the moment on demand for Betas and Gammas; DJB are able to sell all that they produce. Required (i) Formulate a linear programming model using the above data where DJB's objective is to maximise total monthly contribution. Use the following notation: x1 = number of Alphas produced and sold per month x2 = number of Betas produced and sold per month x3 = number of Gammas produced and sold per month Z = total monthly contribution () Use suitable Excel spreadsheet for analysis of the model. (ii) Use the Solver tool to find the optimal solution of your model and using the Answer Report give information to DJB on the production levels of their three products which will lead to maximum contribution. State the amount of their total monthly contribution. If there is a slack of processing time at either Stage 1 or Stage 2, state the number of those hours. (iii) Use information from the Sensitivity Report to investigate the effect on DJB's total contribution that results from: (a) an increase of 20 hours per month in the process time at Stage 1; (b) an increase of 20 hours per month in the process time at Stage 2; (c) an increase of 10 units in the anticipated monthly demand for Alphas; (d) receiving a monthly order, which must be met, for 10 Gammas.

im confused on getting the answers for iii) a,b,c,d

i dont know what i need to do on solver to get these answers