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_4 or s. ~p_22. ~s_4. p_22 <-> q_22.
s can be inferred via the disjunctive syllogism rule. ~p_22 and ~s_4 can be inferred via the conjunction rule. ~s_4 and ~p_22 can be inferred via the conjunction rule. p_22 -> q_22 can be inferred via the biconditional elimination rule. q_22 -> p_22 can be inferred via the biconditional elimination rule. ~q_22 can be inferred via the biconditional elimination rule.