QUESTION 1 (25 Marks) Francis, the owner of Automobile Service Centre is interested in determining the fixed and variable costs of performing a standard oil change. Since the oil changes are fairly standard, each one taking about the same amount of time and using about the same amount of grease, paper towel, etc. the total monthly cost includes the salaries of the two service persons, depreciation on the facility and equipment, utilities and supplies such as grease and wipes. Data for the past eight months are as follows: Month | May June July August September October November December Number of oil changes 1,200 1,400 1,370 1,250 890 900 850 700 Total cost RM7,250 7,950 8,300 7,425 5,730 5,730 5,450 5,150 Required: a) Calculate the variable rate for oil changing services using the high-low method. (4 marks) b) Calculate the fixed monthly cost of oil changing services using the high-low method. (3 marks) c) Write the cost formula for the oil changing services showing the fixed cost and the variable rate. (3 marks) d) Calculate the predicted cost for January for 1,000 oil changes using the high-low formula. (3 marks) e) Explain the important of knowledge of cost behaviour for managerial decision making. Provide an example to illustrate your answer. (6 marks) f) Distinguish between mixed cost and step cost. Give an example for each cost. (6 marks)