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_10 -> p_13. r. p_13 -> q_10. p_13 -> ~t. t.
~p_13 can be inferred via the modus tollens rule. q_10 -> ~t can be inferred via the transitivity rule. r and t can be inferred via the conjunction rule. t and r can be inferred via the conjunction rule. q_10 <-> p_13 can be inferred via the biconditional introduction rule. p_13 <-> q_10 can be inferred via the biconditional introduction rule.