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: If William were a politician, then Barbara is rich. For all x_6, if x_6 goes running, then x_6 is a nurse. For all x_6, if x_6 were rich, then x_6 is running.
For all x_6, if x_6 were rich, then x_6 is a nurse can be inferred via the universal transitivity rule.