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For the base case in this section, as a percentage of sales, COGS =68 percent, SGA=13 percent, R&D=2.0 percent. Depreciation, Interest expense are fixed as stated. Tax Rate is 19 percent. 1.a Given the following case, calculate the independent effects of a 1 percent increase in Gross Margin, a 1 percent decrease in the TaxRate, and a 5 percent increase in Sales