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: t -> p. p_4 -> t. ~p. s_2.
~t can be inferred via the modus tollens rule. p_4 -> p can be inferred via the transitivity rule. ~p and s_2 can be inferred via the conjunction rule. s_2 and ~p can be inferred via the conjunction rule.