What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall z: U_4(z) -> W_1(z). forall z: W_1(z) -> U_4(z). W_1(c) -> p_2.
forall z: U_4(z) <-> W_1(z). forall z: W_1(z) <-> U_4(z).