A statistics teacher wants to know how her students feel about an introductory statistics course. She decides to administer a survey to a random sample of students taking the course. She has several sampling plans to choose from. Name the sampling strategy in each. a. There are four ranks of students taking the class: freshmen. sophomores, juniors, and seniors. Randomly select 15 students from each class rank. b. Randomly select a class rank (freshmen, sophomores, juniors, and seniors) and survey every student in that class rank. c. Each student has a nine-digit student number. Randomly choose 60 numbers. d. Using the class roster, select every fifth student from the list. (2 points) Explain why the second plan suggested above, sampling all students from one class rank, might be biased. Be sure to name the kind(s) of bias you describe.