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 is happy. Michael is running if and only if Robert is happy. For all z, z is not an artist.
If Michael goes running, then Robert is happy. If Robert were happy, then Michael is running. For all z, if z were an artist, then z is happy. For all z, if z were happy, then z is an artist. For all z, z is not happy.