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 -> q_2. t_2 or t. t_2 <-> q_2. q.
t_2 -> q_2 can be inferred via the biconditional elimination rule. q_2 -> t_2 can be inferred via the biconditional elimination rule.