In row 8 calculate the total sales revenue for each of the different Sales Volumes using the sales mix options selected in B3 and B4 (do not use the sales mix from the CVP sheet.) Also,Complete the variable costs table for the different sales volumes (B11:G14) using the sales mix options selected in B3 and B4.ThenIn row 17 calculate Profit Before Tax (Contribution Margin - Fixed Costs) for each sales volume (this will return a negative value where the unit volume is less than the break-even)