Question: MODELING WITH DATA Annual retail sales in the United States from 1990 through the year 2000 (in billions of dollars) are given in the following table:
a. Let t 0 correspond to 1990 and use QuadReg to find a second-degree polynomial regression model based on the given data.
b. Plot the graph of the function found in part (a) in the viewing window [0, 10] × [0, 1000].
c. What were the annual retail sales in the United States in 1999 (t = 9)?
d. Approximately how fast were the retail sales changing in 1999 (t = 9)?