Step-by-step explanation:
To find the linear regression model for Amazon's operating expenses as a function of net sales, we calculate the slope and intercept of the regression line using the given data. The model is then expressed as \(E = 0.2807S + 0.7779\).
For net sales of $90 billion, the operating expenses would be approximately $25 billion.
To assess the reasonableness of the linear model, we can analyze the correlation coefficient \(r\) and visually inspect the graph. If \(r\) is close to 1 or -1, or if the data points cluster around the regression line, the linear model is reasonable. I think
