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What Color Is Your Car? The most popular colors for cars and light trucks vary with region and type of vehicle and over time. In North America, silver and white are the most popular choices for midsize cars, silver and black for convertibles and coupes, and white for light trucks. Despite this variation, overall white remains the top choice worldwide for the eighth consecutive year, increasing its lead by \(2 \%\) over the previous year. Here is the distribution of the top colors for vehicles sold globally in 2018: \(\frac{17}{\text {. }}\) CARCOLOR \begin{tabular}{|l|c|} \hline Color & Popularity \\ \hline White & \(39 \%\) \\ \hline Black & \(17 \%\) \\ \hline Gray & \(12 \%\) \\ \hline Silver & \(10 \%\) \\ \hline Natural & \(7 \%\) \\ \hline Red & \(7 \%\) \\ \hline Blue & \(7 \%\) \\ \hline Green & 7 \\ \hline \end{tabular} Fill in the percentage of vehicles that are in green, Make a graph to display the distribution of color popularity.

High School Tobacco Use. Despite the intense anti-smoking campaigns sponsored by both federal and private agencies, smoking continues to be the single- biggest cause of preventable death in the United States. How has the tobacco use of high school students changed over the past few years? For each of several tobacco products, high school students were asked whether they had used each of them in the past 30 days. Here are some of the results: \(\frac{18}{8}\) The first row of the table gives the percentages of high school students who had used any tobacco product, including cigarettes, pipes, cigars, smokeless tobacco, e-cigarettes, hookahs, snus, bidis, or dissolvable tobacco, in the past 30 days for the years 2011-2018. The remaining rows give the percentage of high school students using the most common tobacco products in each of these years. a. Using the information in the first row of the table, draw a bar chart that shows the change in the use of any tobacco product between 2011 and 2018. How would you describe the pattern of change in this usage? b. Draw a bar chart that illustrates the change in usage in these years for the individual tobacco products. If your software allows it, give a single bar chart that contains the information for all products. Otherwise, provide a separate bar chart for each product. c. Using the bar charts in parts (a) and (b), give a simple description of the changes in the use of tobacco products by high school students between 2011 and \(2018 .\)

Choosing Class Intervals. Student engineers learn that, although handbooks give the strength of a material as a single number, in fact the strength varies from piece to piece. A vital lesson in all fields of study is that "variation is everywhere." Here are data from a typical student laboratory exercise: the load in pounds needed to pull apart pieces of Douglas fir 4 inches long and \(1.5\) inches square: The data sets in the One-Variable Statistical Calculator applet on the text website include the "pulling wood apart" data given in this exercise. How many class intervals does the applet choose when drawing the histogram? Use the applet to make several histograms with a larger number of class intervals. Are there any important features of the data that are revealed using a larger number of class intervals? Which hist ogram do you prefer? Explain your choice.