Consider the following premises. It is snowing if and only if it is sunny. It is not sunny. If it is sunny, then it is snowing. Elisabeth is taking a plane if and only if it is snowing. Can we infer the following from them? Elisabeth is taking a plane.
 From the fact that it is snowing if and only if it is sunny we can infer that if it snows, then it is sunny. From the fact that if it snows, then it is sunny, and that if it is sunny, then it is snowing we can infer that it is snowing if and only if it is sunny. From the fact that it is snowing if and only if it is sunny, and that it is not sunny we can infer that it is not snowing. Finally, from the fact that Elisabeth is taking a plane if and only if it is snowing, and that it is not snowing we can infer that Elisabeth is not taking a plane, which contradicts that Elisabeth is taking a plane. Therefore, the answer is no.