A local furniture manufacturer produces two types of kitchen cabinets, namely type A and B. Each unit of type A requires 2.5 hours of assembly, and type B requires 5 hours of assembly. The total assembly hours available are 400. The total number of cabinets produced each day is not less than 100 units. Due to the demand restriction in the market, the number of type B cabinets must be at most equal to the number of units of type A cabinets produced. It is known that the costs of producing each unit of type A and B cabinets are RM40 and RM60 respectively. Formulate the above problem as a Linear Programming problem. (6 marks) Graph and show the feasible region of the above problem clearly. (marks) Find the optimal solution and the associated minimum total cost. (12 marks)