The Student Learning Center believes that some students are dissatisfied with the setup of the current computer labs, and that changes could be made to increase student satisfaction. Two different sampling plans were used.

Plan 1 Since all the task force members had classes in the school of music, each student in the task force could administer the survey to students before and after classes. Each task force member would be responsible for completing 25 surveys. Which sampling method does plan 1 use?

Plan 2 Each task force member could be assigned to collect 25 surveys from either undergraduate or graduate students. Because 75% of students are undergraduates, three task force members would collect surveys from undergraduates and one from graduate students. Which sampling method does this plan use?