Consider the following premises. There is at least one x_7 for which if x_7 drives a car, then x_7 is taking a plane. For all x_7, x_7 will climb a mountain if and only if x_7 will drive a car. For all x_7, x_7 will read a book or x_7 will climb a mountain. For all x_7, if x_7 reads a book, then x_7 is driving a car. Can we infer the following from them? There is at least one x_7 for which x_7 will take a plane.
 From the fact that for all x_7, x_7 will climb a mountain if and only if x_7 will drive a car we can infer that for all x_7, if x_7 climbs a mountain, then x_7 is driving a car. From the fact that for all x_7, if x_7 reads a book, then x_7 is driving a car, that for all x_7, if x_7 climbs a mountain, then x_7 is driving a car, and that for all x_7, x_7 will read a book or x_7 will climb a mountain we can infer that for all x_7, x_7 will drive a car. Finally, from the fact that there is at least one x_7 for which if x_7 drives a car, then x_7 is taking a plane, and that for all x_7, x_7 will drive a car we can infer that there is at least one x_7 for which x_7 will take a plane. Therefore, the answer is yes.