A-Zone Media sells two models of e-readers. The budgeted price per unit for the wireless model is $192 and the budgeted price per unit for the wireless and cellular model is $416. The master budget called for sales of 10,000 wireless models and 2,500 wireless and cellular models during the current year. Actual results showed sales of 7,500 wireless models, with a price of $200 per unit, and 4,000 wireless and cellular models, with a price of $400 per unit. The standard variable cost per unit is $80 for a wireless model and $160 for a wireless and cellular model.

a. Compute the activity variance for these data

b. Compute the mix and quantity variance for these data