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 <-> p_11. p_11 <-> p.
p -> p_11 can be inferred via the biconditional elimination rule. p_11 -> p can be inferred via the biconditional elimination rule. p_11 -> p can be inferred via the biconditional elimination rule. p -> p_11 can be inferred via the biconditional elimination rule.