Consider the following premises. It is snowing. For all x, x is a police officer. If Charles were a nurse, then David is not a police officer. Can we infer the following from them? It is snowing and Charles is not a nurse.
 From the fact that for all x, x is a police officer we can infer that David is a police officer. From the fact that if Charles were a nurse, then David is not a police officer, and that David is a police officer we can infer that Charles is not a nurse. Finally, from the fact that it is snowing, and that Charles is not a nurse we can infer that it is snowing and Charles is not a nurse. Therefore, the answer is yes.