Sheridan Company sells two types of computer hard drives. The sales mix is 30% (Q-Drive) and 70% (Q-Drive Plus) based upon quantity of units sold. Q-Drive has a unit variable cost of $120 and a selling price of $210. Q-Drive Plus has a unit variable cost of $100 and a selling price of $180. The weighted-average unit contribution margin for Sheridan is
O $87.
O $105.
O $210.
O $83.