ABC Ltd manufactures Model X, Model Y and Model Z, which are non-customised products. ABC Ltd made a 540,000 profit last year and proposes an identical plan for the coming year. The relevant data for last year are presented below: Actual production and sales (units) Potential demand (units) Total cost per unit (/unit) Selling price per unit (/unit; 30% on cost) Labour hour per unit (hour/unit) Model X Model Y Model Z 40,000 60,000 40,000 45,000 75,000 60,000 20 10 10 26 13 13 3 1 3 Fixed costs were 600,000 for the year, absorbed on labour hours which were fully utilised for the production achieved. Discuss how the product mix decisions are different when capacity constraints exist and do not exist. Explain your answer for each case and provide an example to illustrate your answer (11 marks)