Acorporation has used a traditional cost accounting system to apply quality control costs uniformly to all products at a rate of 15% of direct labor cost. monthly direct labor cost for its main product is $30,000. in an attempt to distribute quality control costs more equitably, the corporation is considering activity-based costing (abc). the monthly data shown below have been gathered for the main product. the three activities are (1) incoming materials inspection, (2) in-process inspection, and (3) product certification. costs are to be allocated to each activity on the basis of cost drivers. the monthly quality control cost assigned to the main product using abc is