Consider the following premises. For all x_2, x_2 will take a plane. For all x_2, x_2 will cook. For all x_2, if x_2 takes a plane, then x_2 is an office clerk. Can we infer the following from them? There is at least one x_2 for which x_2 is not an office clerk.
 From the fact that for all x_2, if x_2 takes a plane, then x_2 is an office clerk, and that for all x_2, x_2 will take a plane we can infer that for all x_2, x_2 is an office clerk. From the fact that for all x_2, x_2 will cook, and that for all x_2, x_2 is an office clerk we can infer that for all x_2, x_2 will cook and x_2 is an office clerk. Finally, from the fact that for all x_2, x_2 will cook and x_2 is an office clerk we can infer that for all x_2, x_2 will cook, which contradicts that There is at least one x_2 for which x_2 is not an office clerk. Therefore, the answer is no.