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Red Baron, Inc., is a new competitor in the production of airplane propellers. Red Baron has to train its employees in the process of making propellers. To increase the speed of learning, Red Baron will give a bonus to the employee with the lowest cumulative average time per unit after eight units are completed. Lucy took 50 hours to complete the first unit, and she is subject to an 80% learning curve. Sally took 60 hours to complete the first unit, and she is subject to a 70% learning curve. Marcy took 40 hours to complete the first unit, and she is subject to a 90% learning curve. Patty took 55 hours to complete the first unit, and she is subject to a 75% learning curve. Which employee will receive the bonus?