1. A state group is interested in whether voters would support lowering the legal drinking age to 18. A simple random of 25 voters is selected from each country in the state and asked whether they approved of lowering the drinking age . This is an example of
a) Systematic sampling
b) Multistage sampling
c) A simple random sample
d) Stratified sampling
2. A business magazine mailed a questionaire to the human resource directors of all the Fortune 500 companies, and received respones from 32% of them. Those responding reported that they did not find that such surveys intruded significantly on their workday. ( identify the largest source of bias).
3. Suppose you are conducting a survey regarding illicit drug use among sophomorse in the BaltimoreSchool District. You obtain a random sample of 12 schools within the district and have the teachers verbally administer the surveys to all sophomores ( identify the largest source of bias).