Consider the following premises. For all x_15, x_15 will not listen to a song. There is at least one x_15 for which x_15 will take a plane or x_15 will play tennis. For all x_15, if x_15 takes a plane, then x_15 is listening to a song. For all x_15, x_15 will play tennis if and only if x_15 will listen to a song. Can we infer the following from them? There is at least one x_15 for which x_15 is excited.
 From the fact that for all x_15, x_15 will play tennis if and only if x_15 will listen to a song we can infer that for all x_15, if x_15 plays tennis, then x_15 is listening to a song. From the fact that for all x_15, if x_15 takes a plane, then x_15 is listening to a song, that for all x_15, if x_15 plays tennis, then x_15 is listening to a song, and that there is at least one x_15 for which x_15 will take a plane or x_15 will play tennis we can infer that there is at least one x_15 for which x_15 will listen to a song. From the fact that there is at least one x_15 for which x_15 will listen to a song we can infer that there is at least one x_15 for which x_15 will listen to a song or x_15 is excited. Finally, from the fact that there is at least one x_15 for which x_15 will listen to a song or x_15 is excited, and that for all x_15, x_15 will not listen to a song we can infer that there is at least one x_15 for which x_15 is excited. Therefore, the answer is yes.