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 will listen to a song if and only if x is a lawyer. For all x, x will listen to a song or x will not take a plane.
For all x, if x takes a plane, then x is listening to a song. For all x, if x listens to a song, then x is a lawyer. For all x, if x were a lawyer, then x is listening to a song.