Consider the following premises. For all x_11, x_11 is a sailor or x_11 is an electrician. For all x_11, x_11 is not a sailor or x_11 is a bartender. For all x_11, if x_11 were curious, then x_11 is an electrician. For all x_11, x_11 is not a soldier. For all x_11, x_11 is a soldier if and only if x_11 is curious. For all x_11, if x_11 were an electrician, then x_11 is curious. Can we infer the following from them? If we can, name the inference rule being used: There is at least one x_11 for which x_11 is not a bartender.
 From the fact that for all x_11, if x_11 were curious, then x_11 is an electrician, and that for all x_11, if x_11 were an electrician, then x_11 is curious we can infer that for all x_11, x_11 is curious if and only if x_11 is an electrician via universal biconditional introduction. From the fact that for all x_11, x_11 is a soldier if and only if x_11 is curious, and that for all x_11, x_11 is not a soldier we can infer that for all x_11, x_11 is not curious via universal biconditional elimination. From the fact that for all x_11, x_11 is curious if and only if x_11 is an electrician, and that for all x_11, x_11 is not curious we can infer that for all x_11, x_11 is not an electrician via universal biconditional elimination. From the fact that for all x_11, x_11 is a sailor or x_11 is an electrician, and that for all x_11, x_11 is not a sailor or x_11 is a bartender we can infer that for all x_11, x_11 is an electrician or x_11 is a bartender via universal resolution. Finally, from the fact that for all x_11, x_11 is an electrician or x_11 is a bartender, and that for all x_11, x_11 is not an electrician we can infer that for all x_11, x_11 is a bartender via universal disjunctive syllogism, which contradicts that There is at least one x_11 for which x_11 is not a bartender. Therefore, the answer is no.