Consider the following premises. For all x_20, if x_20 were excited, then x_20 is a lawyer. If Charles were a lawyer, then Jessica is listening to a song. If Jessica listens to a song, then Susan is playing tennis. If James were poor, then Charles is excited. If Susan plays tennis, then James is poor. Can we infer the following from them? If is not true that Charles is excited if and only if Jessica is listening to a song.
 From the fact that for all x_20, if x_20 were excited, then x_20 is a lawyer we can infer that if Charles were excited, then Charles is a lawyer. From the fact that if Jessica listens to a song, then Susan is playing tennis, and that if Susan plays tennis, then James is poor we can infer that if Jessica listens to a song, then James is poor. From the fact that if Charles were excited, then Charles is a lawyer, and that if Charles were a lawyer, then Jessica is listening to a song we can infer that if Charles were excited, then Jessica is listening to a song. From the fact that if Jessica listens to a song, then James is poor, and that if James were poor, then Charles is excited we can infer that if Jessica listens to a song, then Charles is excited. Finally, from the fact that if Charles were excited, then Jessica is listening to a song, and that if Jessica listens to a song, then Charles is excited we can infer that Charles is excited if and only if Jessica is listening to a song, which contradicts that If is not true that Charles is excited if and only if Jessica is listening to a song. Therefore, the answer is no.