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: forall y: U(y) -> R_4(y). forall y: R_4(y) -> U(y). forall y: R_4(y) -> Q(y). forall y: Q(y) -> U(y).
forall y: U(y) -> Q(y) can be inferred via the universal transitivity rule. forall y: R_4(y) -> U(y) can be inferred via the universal transitivity rule. forall y: Q(y) -> R_4(y) can be inferred via the universal transitivity rule. forall y: U(y) <-> R_4(y) can be inferred via the universal biconditional introduction rule. forall y: R_4(y) <-> U(y) can be inferred via the universal biconditional introduction rule.