Consider the following premises. For all x_9, if x_9 cooks, then x_9 is a mechanic. For all x_9, x_9 is a soldier if and only if x_9 is a mechanic. For all x_9, if x_9 were happy, then x_9 is cooking. There is at least one x_9 for which x_9 will take a plane if and only if x_9 is happy. For all x_9, x_9 is not a soldier. Can we infer the following from them? There is at least one x_9 for which x_9 will not take a plane.
 From the fact that for all x_9, if x_9 were happy, then x_9 is cooking, and that for all x_9, if x_9 cooks, then x_9 is a mechanic we can infer that for all x_9, if x_9 were happy, then x_9 is a mechanic. From the fact that for all x_9, x_9 is a soldier if and only if x_9 is a mechanic, and that for all x_9, x_9 is not a soldier we can infer that for all x_9, x_9 is not a mechanic. From the fact that for all x_9, if x_9 were happy, then x_9 is a mechanic, and that for all x_9, x_9 is not a mechanic we can infer that for all x_9, x_9 is not happy. Finally, from the fact that there is at least one x_9 for which x_9 will take a plane if and only if x_9 is happy, and that for all x_9, x_9 is not happy we can infer that there is at least one x_9 for which x_9 will not take a plane. Therefore, the answer is yes.