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 or q_4. ~t. q_4 -> u. t <-> p.
t -> p can be inferred via the biconditional elimination rule. p -> t can be inferred via the biconditional elimination rule. ~p can be inferred via the biconditional elimination rule.