What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_9, x_9 is a writer if and only if x_9 is a bartender. There is at least one x_9 for which if x_9 were a writer, then x_9 is a sailor. For all x_9, if x_9 were a sailor, then x_9 is a bartender.
There is at least one x_9 for which if x_9 were a writer, then x_9 is a bartender. For all x_9, if x_9 were a writer, then x_9 is a bartender. For all x_9, if x_9 were a bartender, then x_9 is a writer.