Determine which sampling method is used in the next 3 cases, whether it is a:

Simple random sampling, Systematic random sampling, Stratified random

sampling, or Cluster sampling.

a. The research team wanted to conduct a survey about the performance of

faculty members in Prasetiya Mulya. To start the survey, 3,000

undergraduate students in Prasetiya Mulya is alphabetically ordered. Then,

the research team selects every 10th student in the list and call each of them

respectively.

b. 6 of 50 states in United States of America are selected to conduct a research

about their political preference. From those 6 states, 1,000 respondents

from each state are randomly asked.

c. Pricewaterhouse Coopers, a respective research company, wanted to

conduct a research about consumer spending on entertainment worldwide

on 2014. In order to create reliable result, the company has categorized all

countries into high-income countries, medium-income countries, and

low-income countries. On each category, 10 countries are selected to be

sampled by the company.