Each time Mayberry Nursery hires a new employee, it must wait for some period of time before the employee can meet production standards. Management is unsure of the learning curve in its operations but it knows the first job by a new employee averages 40 hours and the second job averages 36 hours. Assume all jobs to be equal in size. Assuming the cumulative average-time method, how much time would it take to build the fourth unit? (Round to nearest hour)