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_4 or t_2. ~t. p_4 <-> t.
p_4 -> t can be inferred via the biconditional elimination rule. t -> p_4 can be inferred via the biconditional elimination rule. ~p_4 can be inferred via the biconditional elimination rule.