What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_8, if x_8 were a police officer, then x_8 is a bartender. Thomas is a police officer if and only if John is listening to a song. For all x_8, if x_8 were a bartender, then x_8 is a police officer. John is not listening to a song.
If Thomas were a police officer, then John is listening to a song. If John listens to a song, then Thomas is a police officer. Thomas is not a police officer. For all x_8, x_8 is a police officer if and only if x_8 is a bartender. For all x_8, x_8 is a bartender if and only if x_8 is a police officer.