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 Richard sleeps, then Jessica is a politician. If Joseph were a sailor, then Richard is sleeping. If it snows, then Joseph is a sailor.
If Joseph were a sailor, then Jessica is a politician can be inferred via the transitivity rule. If it snows, then Richard is sleeping can be inferred via the transitivity rule.