Call centers today play an important role in managing dayto- day business communications with customers. Call centers must be monitored with a comprehensive set of metrics so that businesses can better understand the overall performance of those centers. One key metric for measuring overall call center performance is service level, the percentage of calls answered by a human agent within a specified number of seconds. The file ServiceLevel contains the following data for time, in seconds, to answer 50 incoming calls to a financial services call center:

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1. calculate the measures of variation for ungrouped data (range, standard deviation, variance, and coefficient of variation) explain your results.