(3) Consider the following feasible region (in grey): 1 2 3 4 5 11 (a) If the red line represents an isoprofit line for a maximisation problem, what is the optimal solution? (1 mark) (b) If the blue line represents an isoprofit line for a minimisation problem, what is the optimal solution? (1 mark) (c) Are there any potential maximisation or minimisation problems for this feasible region, for which it is possible that = 4, 12 = 0 is the optimal solution? Explain your answer. (1 mark)