Minden Company manufactures a high-quality wooden birdhouse that sells for $25 per unit. Variable costs are $18 per unit, and fixed costs total $180,000. The company sold 50,000 birdhouses to customers during 2018. The president of Minden Company believes the following changes should be made in 2019: 1. the selling price of the birdhouse should be increased by 20% 2. increase advertising by $30,000 Assume these changes are made. Calculate the number of units Minden Company must sell in 2019 in order to break-even