Consider the following premises. For all x_7, x_7 is poor if and only if x_7 will drink water. If Thomas drives a car, then Barbara is poor. Barbara is not drinking water. Can we infer the following from them? If we can, name the inference rule being used: Thomas is not driving a car.
 From the fact that for all x_7, x_7 is poor if and only if x_7 will drink water we can infer that Barbara is poor if and only if Barbara is drinking water via universal instantiation. From the fact that Barbara is poor if and only if Barbara is drinking water, and that Barbara is not drinking water we can infer that Barbara is not poor via biconditional elimination. Finally, from the fact that if Thomas drives a car, then Barbara is poor, and that Barbara is not poor we can infer that Thomas is not driving a car via modus tollens. Therefore, the answer is yes.