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: r_1 -> r. r -> q_12. p_12 -> r_1. p_12 or ~q_12.
r_1 -> q_12 can be inferred via the transitivity rule. p_12 -> r can be inferred via the transitivity rule. q_12 -> p_12 can be inferred via the rewriting rule.