Redfern Audio produces audio equipment including headphones. At the Campus Facility, it produces two wireless models, Standard and Enhanced, which differ both in the materials and components used and in the labor skill required. Data for the Campus Plant for the third quarter follow. StandardEnhancedTotalUnits produced24,0008,00032,000Machine-hours14,4009,60024,000Direct labor-hours18,00018,00036,000Direct materials costs$ 480,000$ 720,000$ 1,200,000Direct labor costs288,000612,000900,000Manufacturing overhead 864,000Total costs $ 2,964,000 Required: Compute the predetermined overhead rate assuming that Redfern Audio uses direct labor costs to allocate overhead costs.