Shannon Company segments its income statement into its North and South Divisions. The companys overall sales, contribution margin ratio, and net operating income are $540,000, 50%, and $43,200, respectively. The North Divisions contribution margin and contribution margin ratio are $157,500 and 75%, respectively. The South Divisions segment margin is $44,000. The company has $81,000 of common fixed expenses that cannot be traced to either division.