Consider the following premises. If Charles climbs a mountain, then Jessica is a police officer. If Barbara were fast, then Charles is climbing a mountain. If Jessica were a police officer, then Barbara is fast. Charles is not climbing a mountain. Barbara is taking a plane if and only if Jessica is a police officer. Can we infer the following from them? Barbara is taking a plane.
 From the fact that if Jessica were a police officer, then Barbara is fast, and that if Barbara were fast, then Charles is climbing a mountain we can infer that if Jessica were a police officer, then Charles is climbing a mountain. From the fact that if Charles climbs a mountain, then Jessica is a police officer, and that if Jessica were a police officer, then Charles is climbing a mountain we can infer that Charles is climbing a mountain if and only if Jessica is a police officer. From the fact that Charles is climbing a mountain if and only if Jessica is a police officer, and that Charles is not climbing a mountain we can infer that Jessica is not a police officer. Finally, from the fact that Barbara is taking a plane if and only if Jessica is a police officer, and that Jessica is not a police officer we can infer that Barbara is not taking a plane, which contradicts that Barbara is taking a plane. Therefore, the answer is no.