Handal Corporation uses activity-based costing to compute product margins. Overhead costs have already been allocated to the company's three activity cost pools--Machining, Order Filling, and Other. The costs in those activity cost pools appear below: Machining$ 6,649 Order Filling$ 17,440 Other$ 5,800 Machining costs are assigned to products using machine-hours (MHs) and Order Filling costs are assigned to products using the number of orders. The costs in the Other activity cost pool are not assigned to products. Activity data appear below: MHs (Machining)Orders (Order Filling) Product O42,200130 Product S18,700960 Finally, sales and direct cost data are combined with Machining and Order Filling costs to determine product margins. Product O4Product S1 Sales (total)$ 70,100$ 76,600 Direct materials (total)$ 31,800$ 21,000 Direct labor (total)$ 30,600$ 31,700 What is the overhead cost assigned to Product S1 under activity-based costing? Multiple Choice a. $13,800 b.$5,307 c.$15,360 d. $20,667