How do you determine if a connection and rules in data management are being used?

Summary:

Content (please ensure you mask any confidential information):

Across the instances, we have some Connections and separately, rules within Data Management that are not currently being used. They were legacy artefacts created during the implementation project.

1. For connections, Is there a way to determine whether the connections are possibly used?
2. In data management, how would one assess whether rules are used somewhere? I know we can check when they were last run in process details in data management and there I can see that they may have only been run during implementation project. However we are not sure if whether they are linked to a model or rule that was set up (i.e . whether they are getting triggered by certain rule/rulset), but the model was parked for the time being.