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: t -> u. u -> p_10. ~p_10. p_10 <-> t.
~u can be inferred via the modus tollens rule. t -> p_10 can be inferred via the transitivity rule. p_10 -> t can be inferred via the biconditional elimination rule. t -> p_10 can be inferred via the biconditional elimination rule. ~t can be inferred via the biconditional elimination rule.