What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? s_2 -> p_3. t -> s_2. u <-> s_2. ~u. p_3 -> t.
s_2 -> t. t -> p_3. p_3 -> s_2. u -> s_2. s_2 -> u. ~s_2.