Estimating flexible selling expense budget and computing sales volume variance. Seattle Products estimates that it will incur the following selling expenses next period:   a. Derive the cost equation...

Estimating flexible selling expense budget and computing sales volume variance. Seattle Products estimates that it will incur the following selling expenses next period:

a. Derive the cost equation for selling expenses.

b. Assume that Seattle sells 50,000 units during the period. Budgeted sales totaled 65,000 units at a budgeted sales price of $5.50 per unit. Prepare a variance report to show the difference between the master budget and the flexible budget.