What type of sampling are these?

Valentine is interesting in sampling UTA College of Education Masters students about their experience in the program. Valentine contacts the registrar and gets a list of all the students enrolled in the program. She then selects every 10th person on the list to participate. Robbie has a population of individuals who went to a summer institute on teaching. He puts all the participants names in a hat and randomly draws 50 people to interview. UTA is interested in developing a PhD program in education. To help build the program the Dean specifically seeks out Deans from other schools to interview who have successful PhD programs in education. Jack is interested in determining people's favorite fast-food restaurants. Based on a previous survey, Jack knows 80% of the campus enjoys Jack-in-the-Box and 20% of campus enjoys Mcdonalds