Forms, Inc. wants to sell a sufficient quantity of products to earn a profit of $40,000. If the unit sales price is $10, unit variable cost is $8, and total fixed costs are $80,000, how many units must be sold to earn income of $40,000?
a) 60,000 units
b) 40,000 units
c) 15,000 units
d) 600,000 units