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 z, z will cook if and only if z will play a game. For all z, if z listens to a song, then z is playing a game.
For all z, if z cooks, then z is playing a game can be inferred via the universal biconditional elimination rule. For all z, if z plays a game, then z is cooking can be inferred via the universal biconditional elimination rule.