Consider the following premises. If it rains, then Patricia is reading a book. Patricia is a sailor if and only if it is windy. It is windy if and only if Patricia is reading a book. Patricia is not a sailor. It is snowing. Can we infer the following from them? If we can, name the inference rule being used: It is raining.
 From the fact that Patricia is a sailor if and only if it is windy, and that Patricia is not a sailor we can infer that it is not windy via biconditional elimination. From the fact that it is windy if and only if Patricia is reading a book, and that it is not windy we can infer that Patricia is not reading a book via biconditional elimination. Finally, from the fact that if it rains, then Patricia is reading a book, and that Patricia is not reading a book we can infer that it is not raining via modus tollens, which contradicts that It is raining. Therefore, the answer is no.