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 680,000 $2,788,888 $1,156,000 $ 760,000 $ 272,000 $ 294,000 $ 386,000 The company's contribution margin ratio is closest to: Multiple Choice O 39.0% The company's contribution margin ratio is closest to o o o o