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: s_2 <-> p. ~p -> q. w. t -> ~w. s_2 -> t.
~t can be inferred via the modus tollens rule. s_2 -> ~w can be inferred via the transitivity rule. s_2 -> p can be inferred via the biconditional elimination rule. p -> s_2 can be inferred via the biconditional elimination rule.