The data file RollerCoasters contains data (collected from www.rcdb.com) on the maximum speed (miles per hour) and the maximum height (feet) for each of a sample of roller coasters in the U.S. Enter the data into the Corr/ Regression applet.

a. Identify the type of study: randomized experiment or observational study.
b. Identify the experimental/observational units in this study.
c. Identify the two variables of interest and whether each is categorical or quantitative. Which variable do you think makes more sense to use as the explanatory variable and which as the response variable?
d. Produce a scatterplot and comment on the association between the variables as revealed in the scatterplot. (Remember to comment on form, direction, strength, and unusual observations.)
e. Report the value of the correlation coefficient. Does the value of the correlation coefficient support your answer in part (d)? Explain how you are deciding.