Consider the following premises. If John goes running, then it is windy. If James were a bartender, then John is running. If it is windy, then James is a bartender. If John goes running, then James is a bartender. Can we infer the following from them? If we can, name the inference rule being used: It is windy if and only if John is running.
 From the fact that if John goes running, then James is a bartender, and that if James were a bartender, then John is running we can infer that John is running if and only if James is a bartender via biconditional introduction. From the fact that John is running if and only if James is a bartender we can infer that if James were a bartender, then John is running via biconditional elimination. From the fact that if it is windy, then James is a bartender, and that if James were a bartender, then John is running we can infer that if it is windy, then John is running via transitivity. Finally, from the fact that if it is windy, then John is running, and that if John goes running, then it is windy we can infer that it is windy if and only if John is running via biconditional introduction. Therefore, the answer is yes.