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: p_8 -> q_8. p_8 <-> u. q_8 -> u.
p_8 -> u can be inferred via the transitivity rule. p_8 -> u can be inferred via the biconditional elimination rule. u -> p_8 can be inferred via the biconditional elimination rule.