Calculate the Y-sales approximate using the constants you obtained from the regression analysis (use month 6 and fill in the first 4 columns, then install the correct values for "a" and "b" in the last two columns. Finally, use the formula under the "Y-sales Approximation" to calculate the value you regression equation gives you for the new Sales value. Finally, calculate the difference. Month Y - Sales Actual X - Advertising Actual Y - Sales Approximate Y-difference a b 6 15 1.3 17.4339167169584 -2.433916717 0.997586 12.64333 (From table above) (from table above) (from table above) Use the formula below: Use: from from =G28 +H28*D28 =C28-E28 Reg. Anal Reg Anal