1.6 Choosing classes in a histogram. The data set menu that accompanies the One-Variable Statistical Calculator applet includes a data set called “healing of skin wounds.” Choose these data, then click on the “Histogram” tab to see a histogram.

a. How many classes does the applet choose to use? (You can click on the graph outside the bars to get a count of classes.)

b. Click on the graph and drag to the left. What is the smallest number of classes you can get? What are the lower and upper bounds of each class? (Click on each bar to find out.) Make a rough sketch of this histogram.

c. Click and drag to the right. What is the largest number of classes you can get? How many observations does the class with the highest count have?

d. The choice of classes changes the appearance of a histogram. Drag back and forth until you get the histogram you think best displays the distribution. How many classes did you use?