The overhead allocation rate in Franz Company's job order cost accounting system applies overhead based on direct labor costs. The manufacturing costs for the current year were: direct materials, $108,000; direct labor, $144,000; and factory overhead, $18,000. At year end, the total cost of goods in process is 36,000 which includes 12,000 of direct labor cost. What amount of direct material cost is included in the ending goods in process inventory? Please show calculations so I can help to better understand the problem. thanks