What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? If it is overcast, then it is late. It is late if and only if Richard is cooking. If Richard cooks, then it is snowing. If it is late, then it is overcast. It is not snowing.
Richard is not cooking. It is overcast if and only if it is late. It is late if and only if it is overcast. If it is late, then Richard is cooking. If Richard cooks, then it is late.