4. The sales and cost data for two companies in the transportation industry are as follows: X Company Amount Y Company PercentAmount Percent Sales Variable costs Contribution margin Fixed costs Operating income $120,000 72,000 48,000 36,000 $ 12.000 100 60 $120,000 36,000 84,000 100 30 70 72,000 X Company's degree of operating leverage (DOL) at the current sales volume level is calculated to be