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Nik Fung Manufacturing Co. produces the same mobile phone chargers in two plants - a new plant in Kwun Tong and an older plant in Yau Tong. The following data for the two plants are available: All fixed costs per unit are calculated based on a normal capacity usage consisting of 240 working days. When the number of working days exceeds 240 , overtime charges raise the variable manufacturing costs of additional units by $3.00 per unit in Kwun Tong and $8.00 per unit in Yau Tong. Nik Fung Manufacturing Co. is expected to produce and sell 192,000 mobile phone chargers during the coming year. Taking capacity and other considerations into account, the company's production manager has decided to manufacture 96,000 units at each plant, resulting in a plan in which the Yau Tong plant will operate at a capacity of 320 units per day 300 days, and the Kwun Tong plant will operate at its normal capacity, 400 units per day 240 days. Required: a Assume normal annual capacity usage. Calculate the breakeven point in units for the Kwun Tong and Yau Tong plants respectively. (12 marks) b Calculate the operating income that would result from the production manager's plan to produce 96,000 units at each plant. (8 marks) c Determine how the production of 192,000 units should be allocated between the Kwun Tong and Yau Tong plants to maximize the operating income for Nik Fung manufacturing Co. In your own words, explain the reason(s) and show your calculations in details clearly. (15 marks)