Ringing Solutions produces 12,000 units of a cell phone. The production requires prime costs of $350,000, uses 2,500 machine hours, and takes 1,800 setup hours. The activity rates are $47 per machine hour and $126 per setup hour. What is the unit cost of a cell phone? (Note: Round answer to two decimal places.) $57.86 $40.85 $77.31 $60.95