Cenage.com has a E-book titled "Cases in Financial Management by Brigham, Gapenski, and Klein”

The question is,

Hardin expects both the sales and production managers to question her assumptions, so she would like to know which variables are most critical in the sense that profitability is very sensitive to them. Then, she would like to know just how far off her assumption could be before the change to a tighter credit policy would be incorrect. If you are using the spreadsheet model, do some sensitivity analyses, changing one variable at a time while leaving the others at their base case values. Which variables are most important in terms of their effects on profits, and how large an error could there be in the assumptions which you regard as being most critical before the decision should be reversed?