What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall y: W(y) or W_2(y). ~t. forall y: ~W(y) or U(y). W_2(c_4) <-> t.
W_2(c_4) -> t. t -> W_2(c_4). ~W_2(c_4). forall y: W_2(y) or U(y).