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 -> r_1. p_11 -> t. p <-> r_1. p_11.
t can be inferred via the modus ponens rule. p_11 -> r_1 can be inferred via the transitivity rule. p -> r_1 can be inferred via the biconditional elimination rule. r_1 -> p can be inferred via the biconditional elimination rule.