Sample annual salaries​ (in thousands of​ dollars) for employees at a company are listed. 50  43  46  59  34  34  50  43  46  31  59  50  49
​(a) Find the sample mean and sample standard deviation. ​(b) Each employee in the sample is given a 6​% raise. Find the sample mean and sample standard deviation for the revised data set. ​(c) To calculate the monthly​ salary, divide each original salary by 12. Find the sample mean and sample standard deviation for the revised data set. ​(d) What can you conclude from the results of​ (a), (b), and​ (c)?