The Owner of a Retail Store Randomly Selected the Following

question 95

Essay

The owner of a retail store randomly selected the following weekly data on profits and advertising cost.
$\begin{array}{ccc}\text { Week }&\text { Advertising Cost \$) }&\text { Profit } \$\\1 & 0 & 200 \\2 & 50 & 270 \\3 & 250 & 420 \\4 & 150 & 300 \\5 & 125 & 325\end{array}$
a. Write down the appropriate linear relationship between advertising cost and profits. Which is the dependent variable? Which is the independent variable?
b. Calculate the least squares estimated regression line.
c. Predict the profits for a week when $200 is spent on advertising.
d. At 95% confidence, test to determine if the relationship between advertising costs and profits is statistically significant.
e. Calculate the coefficient of determination.