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: forall x_23: P_16(x_23) <-> Q_6(x_23). forall x_23: W(x_23) -> Q_6(x_23). forall x_23: P_16(x_23) <-> P_23(x_23). forall x_23: ~Q_23(x_23). exists x_23: P_23(x_23) <-> Q_23(x_23).
forall x_23: P_16(x_23) -> Q_6(x_23) can be inferred via the universal biconditional elimination rule. forall x_23: P_16(x_23) -> P_23(x_23) can be inferred via the universal biconditional elimination rule. exists x_23: P_23(x_23) -> Q_23(x_23) can be inferred via the existential biconditional elimination rule. forall x_23: Q_6(x_23) -> P_16(x_23) can be inferred via the universal biconditional elimination rule. forall x_23: P_23(x_23) -> P_16(x_23) can be inferred via the universal biconditional elimination rule. exists x_23: Q_23(x_23) -> P_23(x_23) can be inferred via the existential biconditional elimination rule. exists x_23: ~P_23(x_23) can be inferred via the existential biconditional elimination rule.