Consider the following premises. It is sunny if and only if Sarah is reading a book. If Sarah were curious, then it is sunny. Sarah is not reading a book. If it is sunny, then Sarah is curious. Can we infer the following from them? If we can, name the inference rule being used: Sarah is not curious.
 From the fact that it is sunny if and only if Sarah is reading a book, and that Sarah is not reading a book we can infer that it is not sunny via biconditional elimination. From the fact that if Sarah were curious, then it is sunny, and that if it is sunny, then Sarah is curious we can infer that Sarah is curious if and only if it is sunny via biconditional introduction. Finally, from the fact that Sarah is curious if and only if it is sunny, and that it is not sunny we can infer that Sarah is not curious via biconditional elimination. Therefore, the answer is yes.