What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall x: S(x) <-> U(x). p <-> S(f_4). ~U(f_4).
p -> S(f_4). S(f_4) -> p. forall x: S(x) -> U(x). forall x: U(x) -> S(x).