What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? There is at least one z for which if z drinks water, then z is playing a game. For all z, z will drive a car if and only if z will drink water. For all z, if z plays a game, then z is drinking water. For all z, z will not drive a car.
There is at least one z for which z will drink water if and only if z will play a game. There is at least one z for which z will play a game if and only if z will drink water. For all z, if z drives a car, then z is drinking water. For all z, if z drinks water, then z is driving a car. For all z, z will not drink water.