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: p_11 <-> s. ~t_3 or t. t_3 or r_2. ~p_11. r_2 -> s.
r_2 or t can be inferred via the resolution rule. p_11 -> s can be inferred via the biconditional elimination rule. s -> p_11 can be inferred via the biconditional elimination rule. ~s can be inferred via the biconditional elimination rule.