Consider the following premises. If it is cloudy, then Patricia is working. If Karen plays tennis, then it is cloudy. Karen is playing tennis or Patricia is not working. Can we infer the following from them? If we can, name the inference rule being used: Patricia is working if and only if Karen is playing tennis.
 From the fact that Karen is playing tennis or Patricia is not working we can infer that if Patricia works, then Karen is playing tennis via rewriting. From the fact that if Karen plays tennis, then it is cloudy, and that if it is cloudy, then Patricia is working we can infer that if Karen plays tennis, then Patricia is working via transitivity. Finally, from the fact that if Patricia works, then Karen is playing tennis, and that if Karen plays tennis, then Patricia is working we can infer that Patricia is working if and only if Karen is playing tennis via biconditional introduction. Therefore, the answer is yes.