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: W_3(x). exists x: R(x) -> S(x). forall x: R(x) or T(x). forall x: T(x) -> S(x).
exists x: S(x) can be inferred via the existential disjunction elimination rule.