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: For all x_3, x_3 will not drive a car. For all x_3, x_3 will drive a car if and only if x_3 will listen to a song. There is at least one x_3 for which x_3 is a janitor if and only if x_3 will listen to a song.
For all x_3, if x_3 drives a car, then x_3 is listening to a song can be inferred via the universal biconditional elimination rule. There is at least one x_3 for which if x_3 were a janitor, then x_3 is listening to a song can be inferred via the existential biconditional elimination rule. For all x_3, if x_3 listens to a song, then x_3 is driving a car can be inferred via the universal biconditional elimination rule. There is at least one x_3 for which if x_3 listens to a song, then x_3 is a janitor can be inferred via the existential biconditional elimination rule. For all x_3, x_3 will not listen to a song can be inferred via the universal biconditional elimination rule.