A cellular phone company monitors monthly phone usage. The following data represent the monthly phone use in minutes of one particular
customer for the past 20 months. Use the given data to answer parts (a) and (b).
325 517 424 395 494
396 351 379 408 426
523 421 434 373 456
535 394 437 403 513
(a) Determine the standard deviation and interquartile range of the data.
s=(Round to two decimal places as needed.)