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: Jennifer is listening to a song if and only if Sarah is playing a game. For all x_28, x_28 will take a plane. If Sarah plays a game, then Jennifer is not taking a plane. Jennifer is listening to a song if and only if Patricia is working.
If Jennifer listens to a song, then Sarah is playing a game can be inferred via the biconditional elimination rule. If Jennifer listens to a song, then Patricia is working can be inferred via the biconditional elimination rule. If Sarah plays a game, then Jennifer is listening to a song can be inferred via the biconditional elimination rule. If Patricia works, then Jennifer is listening to a song can be inferred via the biconditional elimination rule.