Consider a master port `livingroom.temperature` and slave with name `livingroom` having a port with id `temperature. Following cases need clarification: 1. adding a master port with the id of a slave port (including slave name) 2. a slave port is added and its id (including slave name) clashes with an existing master port 3. a master port is removed but had the same id as a slave port with id (including slave name) 4. a slave port with id (including slave name) identical to that of a master port is removed Are these ports exposed? What events are triggered?