Consider the following premises. There is at least one x_9 for which if x_9 were an electrician, then x_9 is not a politician. For all x_9, if x_9 were a politician, then x_9 is playing squash. For all x_9, if x_9 plays squash, then x_9 is a politician. For all x_9, x_9 will play squash or x_9 will work. For all x_9, if x_9 works, then x_9 is a politician. Can we infer the following from them? If we can, name the inference rule being used: There is at least one x_9 for which x_9 is not an electrician.
 From the fact that for all x_9, if x_9 plays squash, then x_9 is a politician, and that for all x_9, if x_9 were a politician, then x_9 is playing squash we can infer that for all x_9, x_9 will play squash if and only if x_9 is a politician via universal biconditional introduction. From the fact that for all x_9, x_9 will play squash if and only if x_9 is a politician we can infer that for all x_9, if x_9 plays squash, then x_9 is a politician via universal biconditional elimination. From the fact that for all x_9, if x_9 plays squash, then x_9 is a politician, that for all x_9, if x_9 works, then x_9 is a politician, and that for all x_9, x_9 will play squash or x_9 will work we can infer that for all x_9, x_9 is a politician via universal disjunction elimination. Finally, from the fact that there is at least one x_9 for which if x_9 were an electrician, then x_9 is not a politician, and that for all x_9, x_9 is a politician we can infer that there is at least one x_9 for which x_9 is not an electrician via existential modus tollens. Therefore, the answer is yes.