u . Sales Cost of goods sold Operating expenses Operating income 20x3 $178,400 115,000 50,000 13,400 20X2 $162,500 102,500 50,000 10,000 20X1 $155,500 100,000 45,000 10,500 In comparison to year 20X2 the increase in operating income of 20X3 was primarily caused by ign Multiple Choice the effect of sales growth. the effect of cost of goods sold growth. the effect of margin growth. the answer cannot be derived from the information provided. In comparison to year 20X1, the effect of sales growth on operating income of 20x2 was (ignore taxes): 2 14:32 Multiple Choice sk $473 $431 $6.667 $7,000