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 TVs Monitors 17,640 66,360 $45 $78 20,000 80,000 $50 $79 a. Required: Compute the following variances in terms of the contribution margin. Determine the total sales-mix variance. b. Determine the total sales-quantity variance. Determine the total sales-volume variance. d. What other variances should be considered when assessing the performance of the Sales Manager. c