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 x_6 for which if x_6 listens to a song, then x_6 is an artist. For all x_6, if x_6 were an artist, then x_6 is playing squash. For all x_6, if x_6 were a bartender, then x_6 is listening to a song. For all x_6, if x_6 were rich, then x_6 is a bartender.
For all x_6, if x_6 were rich, then x_6 is listening to a song can be inferred via the universal transitivity rule. There is at least one x_6 for which if x_6 listens to a song, then x_6 is playing squash can be inferred via the existential transitivity rule. There is at least one x_6 for which if x_6 were a bartender, then x_6 is an artist can be inferred via the existential transitivity rule.