Sort the file from largest to smallest Sales revenue. How do I find the lower bound for the upper stratum?

1. Assume that the ABC Company's FYE is 12/31/12. How to check for appropriate sales cutoff and identify any potential errors in sales revenue?
2. How to use Tableau to determine the market segment of sales by product category and consumer market region?

6. Assume that you wish to develop an expectation to compare likely sales levels by month across the three product categories, that is, furniture, office, and technology.

NOTE: I only need help on how to perform the above requirements in Tableau. I do not believe I can include the file here, so I have included snippets of each sheet.