Consider the following premises. For all x_7, x_7 is a sailor if and only if x_7 is fast. For all x_7, x_7 is a sailor or x_7 will listen to a song. For all x_7, x_7 is not fast. Can we infer the following from them? For all x_7, x_7 will listen to a song.
 From the fact that for all x_7, x_7 is a sailor if and only if x_7 is fast we can infer that for all x_7, if x_7 were a sailor, then x_7 is fast. From the fact that for all x_7, if x_7 were a sailor, then x_7 is fast, and that for all x_7, x_7 is not fast we can infer that for all x_7, x_7 is not a sailor. Finally, from the fact that for all x_7, x_7 is a sailor or x_7 will listen to a song, and that for all x_7, x_7 is not a sailor we can infer that for all x_7, x_7 will listen to a song. Therefore, the answer is yes.