Using the base case, calculate the composite effects of a 5 percent increase in sales, a 2 percent decrease in gross margin, and a 5 percent increase is SG&A as percent of sales. Base, Combined. Sales, 2110. cost of goods sold 1224, selling, general, and administrative expense 401, depreciation 121, research and development 112, total costs and expenses 1858, operating income 252, interest expense 34, earnings before income taxes 218, provision for income taxes 44, net income 174