Consider the following premises. For all x_21, x_21 will sleep if and only if x_21 is excited. It is not raining. Jessica is sleeping if and only if it is raining. Can we infer the following from them? Jessica is excited.
 From the fact that for all x_21, x_21 will sleep if and only if x_21 is excited we can infer that Jessica is sleeping if and only if Jessica is excited. From the fact that Jessica is sleeping if and only if it is raining we can infer that if Jessica sleeps, then it is raining. From the fact that if Jessica sleeps, then it is raining, and that it is not raining we can infer that Jessica is not sleeping. Finally, from the fact that Jessica is sleeping if and only if Jessica is excited, and that Jessica is not sleeping we can infer that Jessica is not excited, which contradicts that Jessica is excited. Therefore, the answer is no.