Apublic opinion poll in virginia wants to determine whether registered voters in the state approve of a measure to ban smoking in all indoor restaurants in the interest of public health. the researchers select a simple random sample of 5 counties and then sample all registered voters from each selected county and ask whether they approve or disapprove of the measure. this is an example of:
a. a simple random sample
b. a multistage sample
c. a stratified sample.
d. a cluster sample
e. a systematic sample

C. A stratified sample.

Explanation:

Stratified sample: This is a type of sampling method used in the research method.

In stratified sampling, the experimenter or researcher divides a given population into different groups, named as strata. After diving the population into different groups, the researcher draws a probability sample from each group.

Advantage: Provides greater precision compared to a simple random sample of the same size.

1. state-issued photo ids. provide them for free for those who can't afford them.

2. the system we have seems to be working nearly perfectly. seems like about 31 cases per billion votes cast

3. the national policy for hiring new employees which requires proof of eligibility to work. there are something like 20 types of identification which can be used for this.

c- companies fail to take environmental protection into account. i think