Problem: Last year, Jen and Berry Inc. had sales of $45,000, cost of goods sold (COGS) of 12,000, depreciation charge of $3,000 and selling, general and administrative (SG&A) cost of $10,000. The interest costs were $2,500. Forty percent of SG&A costs are fixed costs. If its sales are expected to be $60,000 this year, what will be the estimated SG&A costs this year? Provide justifications and citations for your responses.