According to the Bureau of Labor Statistics, the average workweek for an adult in the United States in February 2013 was 34.5 hours. Assume the population standard deviation for the number of hours worked per week is 5.0 hours. A random sample of 30 U. S. adults worked an average of 35.1 hours last week.

a. Do the results from this sample support the claim by the Bureau of Labor Statistics?

b. Identify the symmetrical interval that includes 95% of the sample means if the true population mean is 34.5 hours per week.