Consider the following premises. If Sarah were a server, then Thomas is a politician. Thomas is not a politician. James is a musician if and only if Sarah is not a server. Can we infer the following from them? If we can, name the inference rule being used: James is not a musician.
 From the fact that if Sarah were a server, then Thomas is a politician, and that Thomas is not a politician we can infer that Sarah is not a server via modus tollens. From the fact that James is a musician if and only if Sarah is not a server we can infer that if Sarah were not a server, then James is a musician via biconditional elimination. Finally, from the fact that if Sarah were not a server, then James is a musician, and that Sarah is not a server we can infer that James is a musician via modus ponens, which contradicts that James is not a musician. Therefore, the answer is no.