Consider the following premises. For all x_8, if x_8 were a bartender, then x_8 is a taxi driver. For all x_8, x_8 will not make tea. For all x_8, x_8 is a taxi driver if and only if x_8 will make tea. For all x_8, if x_8 takes a plane, then x_8 is a bartender. Can we infer the following from them? If we can, name the inference rule being used: For all x_8, x_8 will not take a plane.
 From the fact that for all x_8, x_8 is a taxi driver if and only if x_8 will make tea, and that for all x_8, x_8 will not make tea we can infer that for all x_8, x_8 is not a taxi driver via universal biconditional elimination. From the fact that for all x_8, if x_8 were a bartender, then x_8 is a taxi driver, and that for all x_8, x_8 is not a taxi driver we can infer that for all x_8, x_8 is not a bartender via universal modus tollens. Finally, from the fact that for all x_8, if x_8 takes a plane, then x_8 is a bartender, and that for all x_8, x_8 is not a bartender we can infer that for all x_8, x_8 will not take a plane via universal modus tollens. Therefore, the answer is yes.