Consider the following premises. For all x_8, if x_8 drives a car, then x_8 is taking a plane. If Richard takes a plane, then Richard is driving a car. For all x_8, if x_8 takes a plane, then x_8 is driving a car. Can we infer the following from them? Richard is driving a car if and only if Richard is taking a plane.
 From the fact that for all x_8, if x_8 takes a plane, then x_8 is driving a car, and that for all x_8, if x_8 drives a car, then x_8 is taking a plane we can infer that for all x_8, x_8 will take a plane if and only if x_8 will drive a car. From the fact that for all x_8, x_8 will take a plane if and only if x_8 will drive a car we can infer that Richard is taking a plane if and only if Richard is driving a car. From the fact that Richard is taking a plane if and only if Richard is driving a car we can infer that if Richard drives a car, then Richard is taking a plane. Finally, from the fact that if Richard drives a car, then Richard is taking a plane, and that if Richard takes a plane, then Richard is driving a car we can infer that Richard is driving a car if and only if Richard is taking a plane. Therefore, the answer is yes.