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_11: P_11(x_11) -> ~Q_11(x_11). forall x_11: P_9(x_11) <-> P_11(x_11). P_9(a_5) <-> p. forall x_11: Q_11(x_11).
P_9(a_5) -> p can be inferred via the biconditional elimination rule. p -> P_9(a_5) can be inferred via the biconditional elimination rule. forall x_11: ~P_11(x_11) can be inferred via the universal modus tollens rule. forall x_11: P_9(x_11) -> P_11(x_11) can be inferred via the universal biconditional elimination rule. forall x_11: P_11(x_11) -> P_9(x_11) can be inferred via the universal biconditional elimination rule.