Consider the following premises. If William sleeps, then William is curious. Sarah is drinking water if and only if William is curious. Susan is climbing a mountain if and only if William is sleeping. Sarah is not drinking water. Can we infer the following from them? Susan is not climbing a mountain.
 From the fact that Sarah is drinking water if and only if William is curious, and that Sarah is not drinking water we can infer that William is not curious. From the fact that if William sleeps, then William is curious, and that William is not curious we can infer that William is not sleeping. Finally, from the fact that Susan is climbing a mountain if and only if William is sleeping, and that William is not sleeping we can infer that Susan is not climbing a mountain. Therefore, the answer is yes.