Consider the following premises. If Jennifer were a soldier, then Joseph is an artist. Joseph is an artist or Jennifer is not a soldier. If Joseph were an artist, then Jennifer is a soldier. Can we infer the following from them? If we can, name the inference rule being used: Joseph is an artist if and only if Jennifer is a soldier.
 From the fact that Joseph is an artist or Jennifer is not a soldier we can infer that if Jennifer were a soldier, then Joseph is an artist via rewriting. Finally, from the fact that if Joseph were an artist, then Jennifer is a soldier, and that if Jennifer were a soldier, then Joseph is an artist we can infer that Joseph is an artist if and only if Jennifer is a soldier via biconditional introduction. Therefore, the answer is yes.