Amazon.com€™s revenues are shown in Table 37 for various years.

Let r be Amazon.com€™s annual revenues (in billions of dollars) at t years since 2010. A model of the situation is r = 13.6t + 34.18.
a. Use technology to construct a scatterplot, and graph the model on the same coordinate system. Does the line come close to the data points?
b. What is the slope? What does it mean in this situation?
c. Use the data in Table 37 to find the approximate rate of change of the revenues for each of the periods 2010€“2011, 2012€“2014, and 2010€“2014. Compare each rate of change with the result you found in part (b).
d. Use the model to predict the revenue in 2019. Have you performed interpolation or extrapolation? Do you have much faith in your prediction?

Table 37 Amazon.com's Annual Revenues Revenue (billions of dollars) Year 2010 2011 2012 2013 2014 34.2 48.1 611 74.5 89.0