AB Corp. had the following income last month. Division A Sales $100,000 $100,000 Variable cost 60,000 40,000 60,000 Contribution margin Fixed expenses Operating income 40,000 20,000 40,000 20,000 20,000 If Division A experiences a 20% increase in sales this month, A's operating income would increase to: O$40,000 O $24,000 $48,000 O $28,000