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_1: ~S_3(y_1). forall y_1: S_3(y_1) or ~W(y_1). forall y_1: S_3(y_1) -> W(y_1). exists y_1: W(y_1) -> S_3(y_1).
exists y_1: ~W(y_1) can be inferred via the existential modus tollens rule. forall y_1: W(y_1) -> S_3(y_1) can be inferred via the universal rewriting rule. exists y_1: W(y_1) <-> S_3(y_1) can be inferred via the existential biconditional introduction rule. exists y_1: S_3(y_1) <-> W(y_1) can be inferred via the existential biconditional introduction rule.