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: For all x_14, x_14 is bored if and only if x_14 is a nurse. If Mary were rich, then Barbara is a nurse. If Joseph listens to a song, then Mary is rich.
If Joseph listens to a song, then Barbara is a nurse can be inferred via the transitivity rule. For all x_14, if x_14 were bored, then x_14 is a nurse can be inferred via the universal biconditional elimination rule. For all x_14, if x_14 were a nurse, then x_14 is bored can be inferred via the universal biconditional elimination rule.