Let us Practice: Sales salaries and commissions are $10,000 when 80,000 units are sold, and $14,000 when 120,000 units are sold. A.) Using the high-low method, what is the variable portion of sales salaries and commission? Be sure to show all your work. Answer: B.) Using the high-low method, what is the fixed portion of sales salaries and commission? Be sure to show all your work