The numbers of courses taught per semester by a random sample of university professors are shown in the histogram. Make a frequency distribution for the data. Then use the table to estimate the sample mean and the sample standard deviation of the data set. 25- 21 20- 17 15- Number of professors 5 3 Number of courses laught per semester Make a frequency distribution for the data. X The sample mean is x = (Round to one decimal place as needed.) The sample standard deviation is s = (Round to one decimal place as needed.)