Consider the following premises. If Jennifer were fast, then Jennifer is driving a car. For all x_5, if x_5 drives a car, then x_5 is fast. Can we infer the following from them? If is not true that Jennifer is driving a car if and only if Jennifer is fast.
 From the fact that for all x_5, if x_5 drives a car, then x_5 is fast we can infer that if Jennifer drives a car, then Jennifer is fast. Finally, from the fact that if Jennifer drives a car, then Jennifer is fast, and that if Jennifer were fast, then Jennifer is driving a car we can infer that Jennifer is driving a car if and only if Jennifer is fast, which contradicts that If is not true that Jennifer is driving a car if and only if Jennifer is fast. Therefore, the answer is no.