4. A company assembles Tractor Model X and Tractor Model Y in Assembly plant at Windsor (Ontario), and Winnipeg (Manitoba) respectively. Model produced in Winnipeg (Manitoba) contributes more profit per unit than the model produced in Windsor (Ontario). However, the Winnipeg plant does not have the capacity to handle the total production of both models. As a result, some of the production need to be produced at Windsor (Ontario) plant. The following table shows the maximum demand for each model for the next year, production capacity for each plant per year, and the profit contribution for each model in production plants. Profit contribution /unit and other related data Model Winnipeg Plant Windsor Plant Maximum Demand Tractor Model X $10 K $ 7K 100,000 units Tractor Model Y $15 K $ 10 K 80,000 units Plant production 120,000 units 60,000 units Capacity a) Formulate the linear programming model for this problem in terms of its objective function, and constraints including the non-negativity constraints. (12) Ans