Consider the following premises. Jennifer is sleeping or Mary is not an astronaut. For all x_12, x_12 will sleep if and only if x_12 will play squash. Can we infer the following from them? If we can, name the inference rule being used: If Mary were an astronaut, then Jennifer is playing squash.
 From the fact that for all x_12, x_12 will sleep if and only if x_12 will play squash we can infer that Jennifer is sleeping if and only if Jennifer is playing squash via universal instantiation. From the fact that Jennifer is sleeping if and only if Jennifer is playing squash we can infer that if Jennifer sleeps, then Jennifer is playing squash via biconditional elimination. From the fact that Jennifer is sleeping or Mary is not an astronaut we can infer that if Mary were an astronaut, then Jennifer is sleeping via rewriting. Finally, from the fact that if Mary were an astronaut, then Jennifer is sleeping, and that if Jennifer sleeps, then Jennifer is playing squash we can infer that if Mary were an astronaut, then Jennifer is playing squash via transitivity. Therefore, the answer is yes.