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 y: Q(y) <-> U(y). exists y: Q(y) -> W_3(y). forall y: U(y) or ~W_3(y).
forall y: W_3(y) -> U(y) can be inferred via the universal rewriting rule. forall y: Q(y) -> U(y) can be inferred via the universal biconditional elimination rule. forall y: U(y) -> Q(y) can be inferred via the universal biconditional elimination rule.