Product S78N's direct materials cost is $49.81 per unit and its direct labor cost is $12.34 per unit. The product sells for $129.00 per unit. According to the activity-based costing system, the product margin per year for product S78N would be closest to: \begin{tabular}{c} $5,471.50 \\ $4,616.50 \\ \hline$5,066.50 \\ \hline$29,632.50 \end{tabular}