Problem 3 Compute the profit (income before taxes) if the net income is $140,000 and the income tax rate is 30 percent. Problem 4 Compute the contribution margin dollars if volume is 20,000 units, price is $10 per unit, and variable cost are 60 percent of revenue. Problem 5 Use the data in Problem 4 to compute the contribution margin dollars if volume increases by 10 percent. Problem 6 Use the data in Problem 4 and compute the contribution margin dollars if price increases by 10 percent. Problem 7 Forecast the upcoming Week 8's volume if a food operation uses a five- week base period