The Really Cool Clothing Company sells its products through a telephone ordering process. Since business is good, the company is interested in studying the way that sales agents interact with their customers. Calls are randomly selected and recorded, then reviewed with the sales agent to identify ways that better service could possibly be provided or that the customer could be directed to other items similar to those they plan to purchase that they might also find attractive. Call handling time (length) in minutes for 20 randomly selected customer calls handled by the same sales agent are as follows: 6, 26, 8, 2, 6, 3, 10, 14, 4, 5, 3, 17, 9, 8, 9, 5, 3, 28, 21, and 4. Calculate the mean and standard deviation of call handling time.