What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: If Charles were rich, then Jennifer is listening to a song. If David reads a book, then Charles is rich. David is reading a book or Jennifer is not listening to a song.
If David reads a book, then Jennifer is listening to a song can be inferred via the transitivity rule. If Jennifer listens to a song, then David is reading a book can be inferred via the rewriting rule.