The American Institute of Certified Tax Planners reports that the average U.S. CPA works 60 hours per week during tax season. Do CPAs in states that have flat state income tax rates work fewer hours per week during tax season? Conduct a hypothesis test to determine if this is so. 

a. Formulate hypotheses that can be used to determine whether the mean hours worked per week during tax season by CPAs in states that have flat state income tax rates is less than the mean hours worked per week by all U.S. CPAs during tax season? 

b. Based on a sample, the mean number of hours worked per week during tax season by CPAs in states with flat tax rates was 55. Assume the sample size was 150 and that, based on past studies, the population standard deviation can be assumed to be σ = 27.4. Use the sample results to compute the test statistic and p-value for your hypothesis test. 

c. At α  = .05, what is your conclusion?