Determine the regression line of $x$ on $y$ giving its coefficients to three significant figures.

Use your regression line from part (a) to estimate the advertising expenditure when $y=7$ Give your answer in hundreds of dollars.

A manager wishes to estimate $y$ when $x=9$ She rearranges the line from part (a) and obtains $y=14.4$

Determine a regression estimate you would use instead, and explain why the manager’s value should not be treated as the regression estimate for predicting $y$ from $x$