What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: If Sarah listens to a song, then it is cold. It is not cold. If it is overcast, then Jessica is a server. Jessica is a server if and only if Sarah is listening to a song.
Sarah is not listening to a song can be inferred via the modus tollens rule. If Jessica were a server, then Sarah is listening to a song can be inferred via the biconditional elimination rule. If Sarah listens to a song, then Jessica is a server can be inferred via the biconditional elimination rule.