M​ & G TV and Appliance Store is a small company that has hired you to perform some management advisory services. The following information pertains to 2017 operations. Sales​ (1,200 televisions) ​$1,200,000 Cost of goods sold ​540,000 Store​ manager's salary per year ​108,000 Operating costs per year ​216,000 Advertising and promotion per year ​24,000 Commissions​ (3.0% of​ sales) ​36,000 What was the variable cost per unit sold for​ 2017? A. ​$450 B. ​$770 C. ​$480 D. ​$30