Q3. All parts in this question are to be solved graphically and not with LINGO. For parts b, c and d, you must show your work, no marks will be given for simply providing the answer. Consider the following problem: Max Z = 3A + 4B St -A + 2B 8 (1) A + 2B 12 (2) 2A + B 16 (3) A, B 0 (a) Solve the following problem using graphical method presented in class. Clearly mark the feasible region and direction of increase/decrease of Z and state what the optimal solution is: value of A, B, Z. (8 marks) (b) What is the range for objective function coefficient for B for which current solution will remain optimal? (5 marks) (c) What is the range for objective function coefficient for B for which point the A = 8, B = 0 will be optimal? (5 marks) (d) What is the range for objective function coefficient for B for which the point A = 0, B = 4 will be optimal? (5 marks)