What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? P(d_1) or ~T_4(d_1). forall y: P(y) -> T_4(y). forall y: T_4(y) -> P(y).
T_4(d_1) -> P(d_1). forall y: P(y) <-> T_4(y). forall y: T_4(y) <-> P(y).