B. This answer did not include sales commissions in the calculation of variable costs.

C. The answer for this problem is found by dividing Fixed Cost by the unit contribution margin. The sales price per unit of $40 Less the variable production costs of $22 Less sales commissiona (5% of sales), which are $2 per unit ($40 × 5%) equals a contribution margin per unit of $16. Total fixed costs are $5,598,720 + $3,732,480, which equals $9,331,200. $9,331,200 ÷ $16 = 583,200 units. Taxes are not relevant when calculating the breakeven point, because at that point, net income will be zero and the tax liability will also be zero.

D. This answer included taxes in the calculation of variable costs. Taxes are not relevant when calculating the breakeven point, because at that point, net income will be zero and the tax liability will also be zero.