12- Sales salaries and commissions are $17,000 when 135,000 units are sold; and $13,000 when 85,000 units are sold. Using the high-low method, what is the variable portion of sales salaries and commission? O $0.05 per unit O $ 0.06 per unit ) Nothing mentioned O $ 0.1 per unit $ 0.075 per unit 0 $0.12 per unit { $0.08 per unit