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 for which x will go running and x will take a plane. For all x, x will listen to a song.
There is at least one x for which x will go running can be inferred via the existential simplification rule. There is at least one x for which x will take a plane can be inferred via the existential simplification rule.