What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall x_4: S_1(x_4) -> Q_4(x_4). exists x_4: P_4(x_4) <-> Q_4(x_4). forall x_4: S_1(x_4) or P_4(x_4).
exists x_4: P_4(x_4) -> Q_4(x_4). exists x_4: Q_4(x_4) -> P_4(x_4).