Question

Math question how do you know what kind of sampling?

One month, the electric company sends surveys with every electric bill. The company requests that customers return the survey with the bill. Which type of sampling method is being used?

voluntary response sampling

convenience sampling

systematic sampling

stratified random sampling

Answer 1

Customers aren't obliged to complete the survey.
so its the 1st choice

If "requests" implies requiring the survey to be returned, then it's convenience sampling.