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: exists z_2: ~T(z_2). forall z_2: T(z_2) <-> R(z_2). forall z_2: R(z_2) -> T(z_2).
exists z_2: ~R(z_2) can be inferred via the existential modus tollens rule. forall z_2: T(z_2) -> R(z_2) can be inferred via the universal biconditional elimination rule. forall z_2: R(z_2) -> T(z_2) can be inferred via the universal biconditional elimination rule. exists z_2: ~R(z_2) can be inferred via the existential biconditional elimination rule.