A wine producer has just finished a study and determined that an additional machine-hour of fermentation capacity would increase wine output by 375 gallons per hour. The input price of a man-hour of labor is $12 per hour, while the input price of a machine-hour of fermentation capacity is $9.40 per hour. If the wine producer is operating at the cost-minimizing level, what is the marginal product of labor? Round your answer to two decimal places