Respuesta :
Answer:
1. does not occur
2. a sample
3. an independent
Step-by-step explanation:
The correct answer for this question would be Occurs, Sample and an independent variable.
What is meant by survey?
A survey is a type of research that involves gathering data from a predetermined group of people in order to get knowledge and insights about a variety of issues.
1) In an observational study, randomization of subjects has to occur to get a lot of diverse information from all the participants.
2) In a survey, randomly a sample is chosen from the population and all the inferences about the population are made from studying this sample only.
3) In a survey a treatment is imposed on all the participants so as to neutralize all the qualities they have which are quite different from the others.
Learn more about survey on:
https://brainly.com/question/25257437
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