A staff analyst for a cafeteria chain wishes to investigate the relation between the number of self-service coffee dispensers (X) in a cafeteria line and sales of coffee (Y) 1. Estimate the linear regression line. Graph the line on the scatter plot. 2. Estimate the quadratic regression equation. Graph the curve on the scatter plot. 3. Does the second order model provide significantly more predictive power than that provided by the straight-line model at a= 0.05? Explain. (Show calculations) 4. Which of the two models do you recommend and why? 5. Would the third order model be any better? Explain showing calculations and computer output. 6. Attach appropriate computer output to support your answers.