Spartan Systems reported total sales of $335,000, at a price of $40 and per unit variable expenses of $22, for the sales of their single product. Total Per Unit Sales $335,000 $40 Variable expenses 184,250 22 Contribution margin 150,750 $18 Fixed expenses 107,000 Net operating income $43,750 What is the amount of contribution margin if sales volume increases by 20%? rev: 03_17_2015_QC_CS-11135 $150,750 $52,500 $35,000 $180,900