Consider the following premises. If Robert were poor, then Patricia is sad. For all z_4, if z_4 were a server, then z_4 is sad. For all z_4, if z_4 were sad, then z_4 is a server. Robert is poor or Patricia is a server. Can we infer the following from them? Patricia is not sad.
 From the fact that for all z_4, if z_4 were sad, then z_4 is a server, and that for all z_4, if z_4 were a server, then z_4 is sad we can infer that for all z_4, z_4 is sad if and only if z_4 is a server. From the fact that for all z_4, z_4 is sad if and only if z_4 is a server we can infer that for all z_4, if z_4 were a server, then z_4 is sad. From the fact that for all z_4, if z_4 were a server, then z_4 is sad we can infer that if Patricia were a server, then Patricia is sad. Finally, from the fact that if Robert were poor, then Patricia is sad, that if Patricia were a server, then Patricia is sad, and that Robert is poor or Patricia is a server we can infer that Patricia is sad, which contradicts that Patricia is not sad. Therefore, the answer is no.