A Small Independent Organic Food Store Offers a Variety of Specialty

A small independent organic food store offers a variety of specialty coffees. To determine whether price has an impact on sales, the managers kept track of how many pounds of each variety of coffee were sold last month. The data, scatterplot, and summary statistics are shown below.
$\begin{array} { | l | l | l | } \hline & \text { PRICE PER POUND } & \text { POUNDS SOLD } \\\hline & \$ 3.99 & 75 \\\hline & \$ 5.99 & 60 \\\hline & \$ 7.00 & 65 \\\hline & \$ 12.00 & 45 \\\hline & \$ 4.50 & 80 \\\hline & \$ 7.50 & 70 \\\hline & \$ 15.00 & 25 \\\hline & \$ 10.00 & 35 \\\hline & \$ 12.50 & 40 \\\hline \text { Mean } & \$ 8.99 & 50 \\\hline & & \\\hline \text { Corandard Deviation } & \$ 8.75 & 54.50 \\\hline & \$ 3.63 & 18.33 \\\hline & & \\\hline\end{array}$

-Using the estimated regression equation,
a. Estimate the monthly sales for a variety of coffee that costs $12 per pound.
b. What is the residual for this estimate? What does it mean?