Brooks Incorporated costs its products using job order costing. The following represents the company's work in process account activity and balances for the month of July. Manufacturing overhead is applied to production using a predetermined overhead rate, using direct labour cost as the cost driver. Work in Process Account Balance, July 1 Direct materials Direct labour Manufacturing overhead Transferred out Balance, July 31 -0- 20,000 30,000 60,000 95,000 15,000 Job 548 was the only job in process at the end of the month. This job had been charged with $3,000 in direct materials cost. I Required: a. Complete the following job order cost card for Job 548. $3,000 Direct materials Direct labour Manufacturing overhead Total cost at July 31 Predetermine overhead rate = manufacturing overhead / direct labor cost = 60,000 / 30,000 = 200% of direct labor cost Cost of direct labor and manufacturing overhead = 15,000 - 3000 - $12000 Direct labor cost - =x* 200% -2.0x b. Determine the total amount of materials cost that was charged to completed jobs during the month