From 1997 through 2004, the value of U.S. exports to Mexico was as shown below. Data are in billions of dollars.
![1445_Data 2.jpg](https://secure.tutorsglobe.com/CMSImages/1445_Data%202.jpg)
a. Fit a linear trend equation to the time series. Using this equation, determine the trend estimate for 2012.
b. Fit a quadratic equation to the time series, then use the equation to determine the trend estimate for 2012.
c. Construct a graph of the time series along with the equations fitted in parts (a) and (b). Which equation appears to better fit the data?