A manufacturer of cedar shingles has supplied the following data: Bundles of cedar shakes produced and sold 280,000 Sales revenue $2,072,000 V ariable manufacturing expense $1,134,000 Fixed manufacturing expense $436,000 Variable selling and administrative expense $238,000 Fixed selling and administrative expense $164,000 Net operating income $100,000 the company's contribution margin ratio is closest to: 66.2% 73.0%. 27.0%. 33.8%