3.19 Use the Simple Random Sample applet. The Simple Random Sample applet allows you to randomly assign experimental units to more than two groups without difficulty. Consider a randomized comparative experiment in which 90 students are randomly assigned to three groups of 30.

a. Use the applet to randomly choose 30 out of 90 students to form the first group. Which students are in this group?

b. There are now 60 students who were not chosen. Use the applet to randomly choose 30 of these remaining students to make up the second group. Which students were chosen?

c. Use the applet to randomly choose the third group. Don’t take the time to write this down. Check that there are only 20 students remaining. These students get Treatment 3. Which students are they?