a. Determine the total cost and cost per unit for each product line, assuming that overhead costs are allocated to each product line using direct labor hours as a companywide allocation base. Also determine the combined cost of all three product lines. b. Determine the total cost and cost per unit for each product line, assuming that an ABC system is used to allocate overhead costs. Determine the combined cost of all three product lines. Note: For all requirements, round intermediate calculations for allocation rates to 2 decimal places and all other calculations to the nearest whole dollar. Round "Cost per Unit" to 2 decimal places. Round your answers for "Total Cost" to the nearest whole dollar amount..