5. The Bureau of Labor Statistics reported that the average yearly income of mid-level managers is greater than $110,000. To challenge this, they took a sample of 81 managers, showing an average yearly income of $100,000. Assume the standard deviation of the population of managers is $36,000. a) in testing the scientist's belief, write the appropriate hypotheses at 5% level of significance. H0: p. >= $110,000 Ha: b) What decision should be made? tail __