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: exists x_7: P_7(x_7) <-> Q_7(x_7). forall x_7: ~P_2(x_7) or Q_7(x_7). forall x_7: W(x_7) -> P_7(x_7). forall x_7: P_2(x_7) or W(x_7).
forall x_7: W(x_7) or Q_7(x_7) can be inferred via the universal resolution rule. exists x_7: P_7(x_7) -> Q_7(x_7) can be inferred via the existential biconditional elimination rule. exists x_7: Q_7(x_7) -> P_7(x_7) can be inferred via the existential biconditional elimination rule.