Richard's Electronics manufactures TVs and Monitors. During April, the following activities occurred: Budgeted units sold Budgeted contribution margin per unit Actual units sold Actual contribution margin per unit Required: TVs Monitors 17,640 66,360 $45 $78 20,000 80,000 $50 $79 Compute the following variances in terms of the contribution margin. A. Determine the total sales-mix variance. B. Determine the total sales-quantity variance. C. Determine the total sales-volume variance. D. What other variances should be considered when assessing the performance of the Sales Manager?