Consider the following premises. For all x_13, x_13 will go running if and only if x_13 will sleep. For all x_13, x_13 will sleep if and only if x_13 will drive a car. For all x_13, x_13 will not go running. For all x_13, x_13 will drive a car or x_13 will not sleep. Can we infer the following from them? If we can, name the inference rule being used: There is at least one x_13 for which x_13 will drive a car.
 From the fact that for all x_13, x_13 will sleep if and only if x_13 will drive a car we can infer that for all x_13, if x_13 drives a car, then x_13 is sleeping via universal biconditional elimination. From the fact that for all x_13, x_13 will drive a car or x_13 will not sleep we can infer that for all x_13, if x_13 sleeps, then x_13 is driving a car via universal rewriting. From the fact that for all x_13, x_13 will go running if and only if x_13 will sleep, and that for all x_13, x_13 will not go running we can infer that for all x_13, x_13 will not sleep via universal biconditional elimination. From the fact that for all x_13, if x_13 sleeps, then x_13 is driving a car, and that for all x_13, if x_13 drives a car, then x_13 is sleeping we can infer that for all x_13, x_13 will sleep if and only if x_13 will drive a car via universal biconditional introduction. Finally, from the fact that for all x_13, x_13 will sleep if and only if x_13 will drive a car, and that for all x_13, x_13 will not sleep we can infer that for all x_13, x_13 will not drive a car via universal biconditional elimination, which contradicts that There is at least one x_13 for which x_13 will drive a car. Therefore, the answer is no.