$4.$ Run Excel$$s Regression tool $($on a new sheet$)$ to develop a simple linear regression model that can be used to predict

sales based on advertising. $($You may delete the duplicate $95\%$ columns.$)$

$5.$ On the Regression Summary Output sheet, write Excel formulas to calculate the expected sales for a quarter with

advertising expenditures of $$32,000,$ and to compute an approximate $68\%$ prediction interval for your estimate based

on the empirical rule. $($Do not use the TREND function.$)$ Format the results as Currency with $0$ decimals.

$6.$ Fill in answers to the questions on the attached sheet.