What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all z_1, z_1 is not a politician. For all z_1, z_1 is an office clerk if and only if z_1 will listen to a song. For all z_1, if z_1 were an office clerk, then z_1 is a politician. There is at least one z_1 for which if z_1 were a politician, then z_1 is listening to a song.
For all z_1, z_1 is not an office clerk. There is at least one z_1 for which if z_1 were an office clerk, then z_1 is listening to a song. For all z_1, if z_1 were an office clerk, then z_1 is listening to a song. For all z_1, if z_1 listens to a song, then z_1 is an office clerk.