Computing Product Costs Using Activity-Based Costing.Stillwater Company identified the following activities, estimated costs for each activity, and identified cost drivers for each activity for this coming year. (These are the first three steps of activity-based costing.)

Z1 Z2 Z3 Direct materials cost per unit $ 100 $ 75 $ 200 Direct labor cost per unit 35 25 70 Overhead cost per unit ? . / . V Product cost per unit $ ? ? Units produced 250 units 500 units 700 unitsZ1 Z2 Z3 Direct materials cost per unit $ 100 $ 75 $ 200 Direct labor cost per unit 35 25 70 Overhead cost per unit ? . / . V Product cost per unit $ ? ? Units produced 250 units 500 units 700 unitsEstimated Annual Estimated Annual Activity Cost Driver Overhead Costs Cost Driver Activity Ordering parts Number of purchase requisitions $ 400,000 5,000 purchase requisitions Tracking inventory of parts Number of parts purchased 560,000 80,000 parts purchased Running machines Machine hours 350,000 7,000 machine hours Inspecting finished products Inspections hours 200,000 1,000 inspection hours Total $ 1,510,000Z1 Z2 Z3 Number of purchase requisitions 50 70 100 Number of parts purchased 4,000 3,300 3,600 Machine hours 330 240 310 Inspections hours 10 50 30Z1 Z2 Z3 Number of purchase requisitions 50 70 100 Number of parts purchased 4,000 3,300 3,600 Machine hours 330 240 310 Inspections hours 10 50 30