3-74. Recently, a store manager tracked the time customers spent in the store from the time they took a number until they left. A sample of 16 customers was selected and the following data (measured in minutes ) were recorded: 15 14 16 14 14 14 13 OO 12 9 7 17 10 15 16 16 a. Compute the mean, median, mode, range, interquartile range, and standard deviation. b. Develop a box and whisker plot for these data. 3-75. Suppose the mean o