Olivet Devices sells two models of fitness devices. The budgeted price per unit for the wireless model is $55 and the budgeted price per unit for the wireless and cellular model is $100. The master budget called for sales of 53,600 wireless models and 13,400 wireless and cellular models during the current year. Actual results showed sales of 39,500 wireless models, with a price of $52 per unit, and 17,100 wireless and cellular models, with a price of $97 per unit. The standard variable cost per unit is $42 for a wireless model and $77 for a wireless and cellular model.

Required:

a. Compute the sales activity variance for these data.

b. Break down the sales activity variance into mix and quantity parts.