Consider the following premises. It is windy. If Elisabeth were a carpenter, then Patricia is a politician. It is windy if and only if Patricia is a politician. Can we infer the following from them? If we can, name the inference rule being used: Patricia is a politician.
 From the fact that it is windy if and only if Patricia is a politician we can infer that if it is windy, then Patricia is a politician via biconditional elimination. From the fact that it is windy we can infer that it is windy or Elisabeth is a carpenter via addition. Finally, from the fact that if it is windy, then Patricia is a politician, that if Elisabeth were a carpenter, then Patricia is a politician, and that it is windy or Elisabeth is a carpenter we can infer that Patricia is a politician via disjunction elimination. Therefore, the answer is yes.