The class roll for a summer section of a statistics class included 100 students. There were no students in this class whose last name began with the letter "Z." Interestingly, every other letter of the alphabet (A through Y) was represented by four student's last names. That is, there were four students with last names that began with the letter "A", four that began with "B", etc. Suppose I want to randomly sample 25 of these 100 students. Which of the following methods would result in a random sample?
◦ Sample the students with the longest last names, because long last names are cool.
◦ Write the student names on slips of paper. Put all 100 slips of paper into a hat and select 25 slips of paper out of the hat, mixing them up between selections.
◦ Sample the first 25 students from the listing of all students.
◦ Write the student names on slips of paper. Select the four slips of paper representing the students with the last names that begin with "A." Put those four slips of paper into a hat, mix them together and pick one of these names out of the hat. Do this for each of the 25 letters of the alphabet.
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