A sales manager for an advertising agency believes that there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression ANOVA shows the following results: ANOVA df SS MS F Significance F Regression 1.00 13555.42 13555.42 156.38 0.00 Residual 8.00 693.48 86.68 Total 9.00 14248.90 What is the value of the standard error of estimate