Final answer:
Questionnaires can be used to determine user opinions, stakeholders, system functions, and user procedures.
Step-by-step explanation:
Questionnaires can be used to ask questions that determine user opinions, determine the stakeholders, define system functions, and detail user procedures. For example, a questionnaire can ask individuals about their opinions on a specific product or service, identify key stakeholders in a project, outline the desired functions of a system, or gather information about specific user procedures.