ABC Co. uses a job-order costing system and applies manufacturing overhead based on machine hours. For 2022, ABC Co. estimated manufacturing overhead to be $54,000, and the estimated machine hours are 9,000. The following information pertains to the month of December 2022: Job 41 Job 42 Job 43 Totals Work in process, December 1 8,000 $ 2,500 $ 1,750 $ 12,250 Direct materials 1,200 800 700 $ 2,700 Direct labour costs 1,500 300 300 S 2,100 Machine hours 320 225 106 'S 645 Actual manufacturing overhead costs incurred in December were $4,000. ABC Co. closes out their manufacturing overhead account at the end of each month. 5 16 Required: a) Calculate the pre-determined overhead rate. 18 b) Calculate the total cost for each job. 19 c) If Job No. 41 was completed during December, what is the balance of Work in Process as at December 31? 20 d) What is the balance of the manufacturing overhead account as at December 31? Is manufacturing overhead over or underapplied? 21 e) ABC Co. is thinking about switching to an activity based costing system. Provide one advantage and one disadvantage of ABC Co. making this switch