Tree Circumference and Height Listed below are the circumferences (in feet) and the heights (in feet) of trees in Marshall, Minnesota (based on data from “Tree Measurements” by Stanley Rice, American Biology Teacher, Vol. 61, No. 9). Is there a correlation? Why should there be a correlation?

Testing for a Linear Correlation. In Exercises 15–24, use the data from Appendix B to construct a scatterplot, find the value of the linear correlation coefficient r, and use a significance level of a 5 0.05 to determine whether there is a significant linear correlation between the two variables. Save your work because the same data sets will be used in the next section.