9. Lots of Highways The number of miles of U.S. urban roadways (millions of miles) for the years 2000–2015 is reported below.6 The years are simplified as years 0 through 15.

a. Draw a scatterplot of the number of miles of roadways in the U.S. over time. Describe the pattern that you see.

b. Find the least-squares line describing these data. Do the data indicate that there is a linear relationship between the number of miles of roadways and the year? Test using a t statistic with a 5.05.

c. Construct the ANOVA table and use the F statistic to answer the question in part

b. Verify that the square of the t statistic in part b is equal to F.

d. Calculate r2. What does this value tell you about the effectiveness of the linear regression analysis?

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Miles of Road- ways (millions) 0.85 0.88 0.89 0.94 0.98 1.01 1.03 1.04 Year - 2000 0 1 2 3 4 5 6 7 Miles of Road- ways (millions) 1.07 1.08 1.09 1.10 1.11 1.18 1.20 1.21 Year - 2000 89 10 11 12 13 14 15