Please help me understand the equations involved to properly answer this question:

A sales manager for an advertising agency believes there is a relationship between the number of contacts that a salesperson makes and the amount of sales dollars earned. A regression analysis shows the following results: Intercept Number of Contacts A NOVA Regression Residual Total Coefficien ts -12.201 2.195 13555.42 693.48 14248.90 Standard Error 6.560 0.176 13555.42 86.68 tStat -1.860 12.505 pvalue 0.100 0.000 nificance F 156.38 33.4. E(X- R): = 2814.4. The 95% prediction interval for a particular person making 30 calls is