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