Consider the following premises. If Karen were an artist, then Joseph is a sailor. Karen is an artist or it is raining. If Charles were poor, then Joseph is not a sailor. Joseph is a sailor if and only if it is raining. Can we infer the following from them? Charles is poor.
 From the fact that Joseph is a sailor if and only if it is raining we can infer that if it rains, then Joseph is a sailor. From the fact that if Karen were an artist, then Joseph is a sailor, that if it rains, then Joseph is a sailor, and that Karen is an artist or it is raining we can infer that Joseph is a sailor. Finally, from the fact that if Charles were poor, then Joseph is not a sailor, and that Joseph is a sailor we can infer that Charles is not poor, which contradicts that Charles is poor. Therefore, the answer is no.