Consider the following premises. If Jessica were a server, then Susan is not poor. Susan is poor. Karen is drinking water if and only if Jessica is a server. If it snows, then Karen is drinking water. Can we infer the following from them? It is not snowing.
 From the fact that if Jessica were a server, then Susan is not poor, and that Susan is poor we can infer that Jessica is not a server. From the fact that Karen is drinking water if and only if Jessica is a server, and that Jessica is not a server we can infer that Karen is not drinking water. Finally, from the fact that if it snows, then Karen is drinking water, and that Karen is not drinking water we can infer that it is not snowing. Therefore, the answer is yes.