Consider the following premises. For all x_4, x_4 is an artist if and only if x_4 will take a plane. For all x_4, x_4 will not take a plane. For all x_4, x_4 will go running if and only if x_4 is an artist. Can we infer the following from them? If we can, name the inference rule being used: For all x_4, x_4 will not go running.
 From the fact that for all x_4, x_4 is an artist if and only if x_4 will take a plane, and that for all x_4, x_4 will not take a plane we can infer that for all x_4, x_4 is not an artist via universal biconditional elimination. Finally, from the fact that for all x_4, x_4 will go running if and only if x_4 is an artist, and that for all x_4, x_4 is not an artist we can infer that for all x_4, x_4 will not go running via universal biconditional elimination. Therefore, the answer is yes.