Metrix Gold Ltd uses a job order costing system, with a predetermined overhead absorption rate based on machine hours. The corporation keeps only one set of books for cost and financial transactions. At the beginning of 2017, the firm estimated its manufacturing overheads for the year at N$65 200 and the machine hours at 9 150. The following are data uses on jobs worked on during December 2017: Details Job A Job B Job C Total N$ N$ N$ N$ W.I.P at 01 December 2017 7 000 3 500 2 500 13 000 Costs incurred in December 2017 - Material Requisitioned from store 2 200 1 000 720 3 920 - Wages according to time sheet 1 500 600 450 2 550 Production activity: machine hours 320 260 140 720 On 31 December 2017, only Job A was completed. Actual manufacturing overheads incurred during December 2017 were N$6 200. REQUIRED; 4.1 Define and compute a pre-determined overhead rate for 2017 (5) 4.2 Calculate the total cost of each job (15) 4.3 Calculate the amount of over/under applied overhead for December 2017 (3) 4.4 What will be the effect of your answer in 4.3? (