Wearing your seatbelt is common, and today it is usually a legal requirement. in the 1950s, however, it was not common nor expected. this example demonstrates that what aspect of culture can change over time?

This shows how a norm can change. While it might not have been expected that one would do such a thing like wearing a seatbelt 60 years ago, expectations and beliefs about what is good and just in a culture can change based upon new research, experiences, and simply the passage of time.