A cement manufacturer has supplied the following data: Tons of cement produced and sold Sales revenue Variable manufacturing expense Fixed manufacturing expense Variable selling and administrative expense Fixed selling and administrative expense Net operating income 315,000 $1,019,000 $ 240,000 $ 337,000 $ 167,600 $ 101,000 $ 173,400 The company's contribution margin ratio is closest to: Multiple Choice 60.0% 66.9% 17.0% 43.4%