The following data are available for the most recent year of operations for Slacker & Sons. The revenue portion of the sales activity variance is $387,000 F Master budget based on actual sales of 168,000 units Revenue Materials Labor Variable manufacturing overhead and administrative costs Fixed manufacturing overhead and administrative costs $4,300,000 868,000 643,000 143,000 480,000 Required a. How many units were actually sold in the most recent period? (Do not round intermediate calculations.) I sales 831,600 units b. Prepare a sales activity variance for the most recent year for Slacker & Sons. (Do not round intermediate calculations. Indicate the effect of each variance by selecting "F" for favorable, or "U" for unfavorable. If there is no effect, do not select either option.) SLACKER& SONS Sales Activity Variance Sales Activity Variance Flexible Budget Master Budget Sales revenue $4,687,000 $387,000 $ 4,300,000 Variable costs Materials Direct labor Variable manufacturing and administrative 868,000 643,000 143,000 $ 1,654,000 $ 2,646,000 Total variable costs Contribution margin Fixed costs $ 4,687,000 Manufacturing overhead and administrative Total fixed costs Operating profits 80,000 $ 80,000 $ 480,000 480,000 $ 2,166,000 $4,207,000