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: There is at least one z for which z will drive a car if and only if z will play a game. For all z, z will drive a car or z will not play a game.
For all z, if z plays a game, then z is driving a car can be inferred via the universal rewriting rule. There is at least one z for which if z drives a car, then z is playing a game can be inferred via the existential biconditional elimination rule. There is at least one z for which if z plays a game, then z is driving a car can be inferred via the existential biconditional elimination rule.