Consider the following premises. For all z_2, z_2 will not listen to a song. For all z_2, z_2 will listen to a song or z_2 will not drink water. For all z_2, if z_2 were an office clerk, then z_2 is drinking water. Can we infer the following from them? There is at least one z_2 for which z_2 is an office clerk.
 From the fact that for all z_2, z_2 will listen to a song or z_2 will not drink water we can infer that for all z_2, if z_2 drinks water, then z_2 is listening to a song. From the fact that for all z_2, if z_2 drinks water, then z_2 is listening to a song, and that for all z_2, z_2 will not listen to a song we can infer that for all z_2, z_2 will not drink water. Finally, from the fact that for all z_2, if z_2 were an office clerk, then z_2 is drinking water, and that for all z_2, z_2 will not drink water we can infer that for all z_2, z_2 is not an office clerk, which contradicts that There is at least one z_2 for which z_2 is an office clerk. Therefore, the answer is no.