Consider the following premises. For all x_9, x_9 is a carpenter. For all z, if z were a carpenter, then z is listening to a song. If Jennifer plays squash, then Charles is listening to a song. Can we infer the following from them? If we can, name the inference rule being used: Charles is listening to a song.
 From the fact that for all x_9, x_9 is a carpenter we can infer that Charles is a carpenter via universal instantiation. From the fact that for all z, if z were a carpenter, then z is listening to a song we can infer that if Charles were a carpenter, then Charles is listening to a song via universal instantiation. From the fact that Charles is a carpenter we can infer that Charles is a carpenter or Jennifer is playing squash via addition. Finally, from the fact that if Charles were a carpenter, then Charles is listening to a song, that if Jennifer plays squash, then Charles is listening to a song, and that Charles is a carpenter or Jennifer is playing squash we can infer that Charles is listening to a song via disjunction elimination. Therefore, the answer is yes.