If fixed costs are $329,000, the unit selling price is $73, and the unit variable costs are $46, what are the old and new break-even sales (units) if the unit selling price increases by $6?

a. 4,507 units and 12,185 units

b. 7,152 units and 9,470 units

c. 12,185 units and 4,507 units

d. 12,185 units and 9,970 units