What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? ~r. forall x_12: R_12(x_12) <-> S_12(x_12). S_12(a_12) <-> t. r <-> t.
S_12(a_12) -> t. r -> t. t -> S_12(a_12). t -> r. ~t. forall x_12: R_12(x_12) -> S_12(x_12). forall x_12: S_12(x_12) -> R_12(x_12).