Consider the following premises. Linda is listening to a song if and only if Elisabeth is bored. If Patricia were a server, then Linda is sleeping. Linda is not listening to a song. If Linda sleeps, then David is not working. David is working. Can we infer the following from them? If we can, name the inference rule being used: Elisabeth is bored.
 From the fact that if Linda sleeps, then David is not working, and that David is working we can infer that Linda is not sleeping via modus tollens. Finally, from the fact that Linda is listening to a song if and only if Elisabeth is bored, and that Linda is not listening to a song we can infer that Elisabeth is not bored via biconditional elimination, which contradicts that Elisabeth is bored. Therefore, the answer is no.