W&W Tax Service offers tax and consulting services to individuals and small businesses. Data for fees and costs for three types of tax returns is presented in the table below. Fixed costs total $56,000.

Type of ReturnSales MixFee ChargedVariable Cost per ReturnEasy50%$ 140$ 80Moderate30%290170Business20%590220

The break-even point in units using the weighted-average contribution margin is:

Select one:

a. 60 units.

b. 174 units.

c. 170 units.

d. 100 units.

e. 400 units.