Having computed measures of central location for various numerical attributes of full-time employees, a human resources manager at Beta Technologies, Inc., is now interested in compiling some statistics on the variability of sample data values about their respective means. Using the data provided in the file P2_1.XLS, assist this manager by computing sample standard deviations for each of the following numerical variables: age, number of years of relevant full-time work experience prior to coming to Beta, number of years of full-time work experience at Beta, number of years of post-secondary education, and salary. Do the rules of thumb apply for any of these variables? In each case explain why the rules of thumb apply or do not apply.