Answer:
(A) $81
Step-by-step explanation:
Sales mix: 30% QD and 70% QD+.
QD Variable costs per unit = $120
QD selling price = $180
QD+ Variable costs per unit = $135
QD+ selling price = $225
The unit contribution for the Q-Drive is:
![U_(QD) = 180-120 = \$ 60](https://img.qammunity.org/2020/formulas/business/college/zd66v3zvkhu309euyy5r842z47qjdzrvpv.png)
The unit contribution for the Q-Drive+ is:
![U_(QD+) = 225-130 = \$ 90](https://img.qammunity.org/2020/formulas/business/college/ehgnwul510nqpgvrndfobdd88kwqea2afm.png)
The weighted-average unit contribution margin for Marigold is
![UC= (0.3*U_(QD))+(0.7*U_(QD+))\\UC= (0.3*60)+(0.7*90)\\UC =\$ 81](https://img.qammunity.org/2020/formulas/business/college/mb9qcqmig1geuqtp4cbnrzp38ahgoutn0y.png)
The answer is (A) $81.