2) Theaverageweeklyearningsoftheplumbersinacityis$748withapopulationstandarddeviationof$21. Assume that we select a random sample of 53 plumbers. a) What is the sampling distribution of the mean...

2) Theaverageweeklyearningsoftheplumbersinacityis$748withapopulationstandarddeviationof$21. Assume that we select a random sample of 53 plumbers. a) What is the sampling distribution of the mean weekly earnings of plumbers? (i.e. What is the sampling distribution of x̅?) b) Find the probability that the sample mean weekly earnings will be between $740 and $745.