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: q <-> t. t <-> q.
q -> t can be inferred via the biconditional elimination rule. t -> q can be inferred via the biconditional elimination rule. t -> q can be inferred via the biconditional elimination rule. q -> t can be inferred via the biconditional elimination rule.