GIVEN: A researcher aims to know the impact of COVID-19 on the companies in Southwest America through interviewing the owner of different companies. The researcher wants to know the average reduction in a company's income one month after the lockdown because of COVID-19. The researcher obtained a list of registered companies through the government as well as additional information like the address and enterprise size. The researcher grouped the companies in terms of size: small, medium, and large enterprises. The researcher initially planned on randomly selecting 200 enterprises per classification. But, the researcher noticed that the cost of transportation is high because the selected enterprises in Southwest America are spread out. So, the researcher instead CHANGED the sampling design by partitioning Southwest America by cities and randomly selecting a sample of cities. Within each selected city, the researcher applied the initial plan of randomly selecting companies based on size. QUESTIONS: 4. In the initial sampling design, what is the sampling frame? a. List of cities b. List of companies c. List of company sizes d. List of registered companies from the government 5. In the final sampling design, what is the type of sampling in the first stage? a. multistage sampling b. cluster sampling c. stratified random sampling d. simple random sampling 6. In the final sampling design, what is the type of sampling frame in the first stage? a. List of cities b. List of companies c. List of company sizes d. List of registered companies from the government