What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x, x is a doctor or x is not rich. For all x, x is rich or x is not a doctor. There is at least one x for which x is not a doctor.
For all x, if x were rich, then x is a doctor. For all x, if x were a doctor, then x is rich.