Consider the following premises. For all x, x will take a plane if and only if x is a police officer. There is at least one x for which x will listen to a song. For all x, if x listens to a song, then x is a police officer. Can we infer the following from them? There is at least one x for which x will take a plane.
 From the fact that for all x, x will take a plane if and only if x is a police officer we can infer that for all x, if x were a police officer, then x is taking a plane. From the fact that for all x, if x listens to a song, then x is a police officer, and that for all x, if x were a police officer, then x is taking a plane we can infer that for all x, if x listens to a song, then x is taking a plane. Finally, from the fact that for all x, if x listens to a song, then x is taking a plane, and that there is at least one x for which x will listen to a song we can infer that there is at least one x for which x will take a plane. Therefore, the answer is yes.