Consider the following premises. Jennifer is a scientist if and only if Robert is sad. Jennifer is working. If Jennifer were a scientist, then Jennifer is not working. Can we infer the following from them? Robert is sad.
 From the fact that if Jennifer were a scientist, then Jennifer is not working, and that Jennifer is working we can infer that Jennifer is not a scientist. From the fact that Jennifer is a scientist if and only if Robert is sad we can infer that if Robert were sad, then Jennifer is a scientist. Finally, from the fact that if Robert were sad, then Jennifer is a scientist, and that Jennifer is not a scientist we can infer that Robert is not sad, which contradicts that Robert is sad. Therefore, the answer is no.