Identify the sampling techniques, sampling frame, and sample size in the following scenarios

3. A researcher wants to understand pet feeding habits among people living in Pakistan. For this, he/she requires a sample size of 200 respondents. The researcher selects 10 cities out of 50 at random. Further, he/she randomly picks out 5 zones per city. From these 50 randomly selected states, he/she then chooses 4 pet-owning households to conduct his research. 4 A researcher has investigated the online classes experience of university students. To examine the study hypotheses, data were randomly collected from university students in Pakistan. The information regarding students was initially collected from the concerned Universities. The questionnaires were subsequently distributed to 350 students of seven different universities located in Pakistan.