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 nurse if and only if x will work. For all x, if x takes a plane, then x is a nurse. There is at least one x for which x will take a plane.
There is at least one x for which x is a nurse. For all x, if x were a nurse, then x is working. For all x, if x works, then x is a nurse.