Consider the following premises. It is late if and only if Patricia is a politician. William is not working. It is not late. William is working if and only if it is windy. Can we infer the following from them? If we can, name the inference rule being used: It is not windy.
 From the fact that it is late if and only if Patricia is a politician, and that it is not late we can infer that Patricia is not a politician via biconditional elimination. Finally, from the fact that William is working if and only if it is windy, and that William is not working we can infer that it is not windy via biconditional elimination. Therefore, the answer is yes.