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: q_6 -> r_6. r_6 -> q. p_14 <-> q. p_14 -> q_6.
q_6 -> q can be inferred via the transitivity rule. p_14 -> r_6 can be inferred via the transitivity rule. p_14 -> q can be inferred via the biconditional elimination rule. q -> p_14 can be inferred via the biconditional elimination rule.