What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all z, z is an artist if and only if z will drink water. There is at least one z for which z is an artist if and only if z will drink water.
For all z, if z were an artist, then z is drinking water. There is at least one z for which if z were an artist, then z is drinking water. For all z, if z drinks water, then z is an artist. There is at least one z for which if z drinks water, then z is an artist.