If they mean different things, the question is a double question. When analyzing data, it is hard to decide whether the answers given refer to both parts or only one part. Interpretation of the information collected is ambiguous. Avoid a double negative. Don't assume too much knowledge.
Most questions assume that a certain amount of knowledge is possessed by the respondent.
Respondents may be too embarrassed to admit their lack of knowledge and take a wild guess. One solution is to ask them to indicate their understanding before asking if they agree or disagree. The current operating hours of the county cannery are 1-5 p.m. Monday through Friday. Word the questions technically correctly. It is important that the information in the question be accurate, leaving no doubt that the researcher accurately comprehends the topic under investigation and that the respondent has appropriate response options to choose from.