In order to understand more about the home internet access of a university with 12768 students, three staff members set out to s
ample a number of students. Below are their plans for sampling the students. Plan 1: One staff member thought that internet access could be different based on the size of the town/city where the student lives, so she obtained a list of all students at the university, divided them into three groups, students living in small-, medium-, and large-sized towns. 10% of students lived in small towns, 40% lived in medium-sized towns, and 50% lived in large-sized towns, so she randomly selected 20 of the students from small towns, 80 from medium-sized towns, and 100 from large-sized towns. Plan 2: The other staff member decided that it would be most efficient to contact students through the online course management system. He randomly sampled 20 courses from the course catalog, and contacted all students in each of these 20 courses through the online course management system. (You may disregard the negligible probability that some student was enrolled in more than one of these 20 courses.) Plan 3: The last staff member had access to a list of students that lived in the dorms, and used a computer program to randomly select 250 students from this list. The staff members took care not attempt to influence student responses in any way. Which of these three plans will result in representative samples of the population of students, on aver
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