Consider the following premises. If Richard plays tennis, then David is a musician. If it rains, then Richard is playing tennis. It is raining or William is excited. William is excited if and only if David is a musician. Can we infer the following from them? David is not a musician.
 From the fact that if it rains, then Richard is playing tennis, and that if Richard plays tennis, then David is a musician we can infer that if it rains, then David is a musician. From the fact that William is excited if and only if David is a musician we can infer that if William were excited, then David is a musician. Finally, from the fact that if it rains, then David is a musician, that if William were excited, then David is a musician, and that it is raining or William is excited we can infer that David is a musician, which contradicts that David is not a musician. Therefore, the answer is no.