You are employed as a head statistician for a company that makes household products, which are sold by part-time salespersons who work during their spare time. The company surveys a cluster sample of four salespeople employed in small town. Let us denote these salespersons A, B, C and D. The sales records (in dollars) for the past six weeks for this cluster sample of four salespersons are shown in the following table:

Week A B C D
1 1774 2205 1330 1402
2 1808 1507 1295 1665
3 1890 2352 1502 1530
4 1932 1939 1104 1826
5 1855 2052 1189 1703
6 1726 1630 1441 1498

Your supervisor has asked your group to prepare a brief report comparing the sales volumes and the consistency of sales of these four salespersons. Use the mean sales for each salesperson to compare the sales volumes, and then choose an appropriate statistical measure to compare the consistency of sales. Make the calculations and write a report. In your calculations, include the mean sales for each salesperson and standard deviation of the sales of each person, and other relevant statistic.