17. Rocko Corporation sells two types of computer hard drives. The sales mix is 30% Premium Drives and 70% Ultra Drives based upon quantity of units sold. The Premium Drive has a unit variable cost of $90 and a unit selling price of $150. The Ultra Drive has a unit variable cost of $105 and a unit selling price of $195. The weighted-average unit contribution margin for Rocko is 4,455 3,300 11,000 7.700