A. An answer of $6,000 results from subtracting all variable costs from the selling price and multiplying that amount by the number of large birdhouses manufactured per day. The throughput contribution margin per unit is not the selling price minus all variable costs.

B. The throughput contribution margin per unit is the selling price minus the totally variable costs, which are usually only direct materials. The selling price of $50 minus the direct materials cost of $7 leaves a throughput contribution margin per unit of $43. Since Bird Watcher can manufacture 200 large birdhouses per day, the throughput contribution margin per day for large birdhouses is $43 * 200, or $8,600.

C. An answer of $6,600 results from subtracting direct materials and direct labor from the selling price and multiplying that amount by the number of large birdhouses manufactured per day. The throughput contribution margin per unit is not the selling price minus direct materials and direct labor.

D. An answer of $5,600 results from subtracting all per unit costs from the selling price per unit, then multiplying that amount by the number of large birdhouses manufactured per day. The throughput contribution margin per unit is not the selling price minus all per unit costs.