The conversational maxim that the professor violates is the relation. It is because professor discusses topics that are not related to the topic that she is going to discuss, which is why she is violating the relation. She focus her attention of discussing events that is happening on her life rather than focusing on teaching the topic that she should be teaching such as the tangents.
The answer is 3 and 4 because 3 shows rain falling into the ocean, and 4 shows the runoff water from rivers and valleys flowing into the ocean.
hopefully this helps u
