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