Consider the following premises. There is at least one x_9 for which x_9 is rich or x_9 will not play squash. For all x_9, x_9 is a lawyer if and only if x_9 is rich. Can we infer the following from them? If we can, name the inference rule being used: There is at least one x_9 for which if x_9 plays squash, then x_9 is a lawyer.
 From the fact that for all x_9, x_9 is a lawyer if and only if x_9 is rich we can infer that for all x_9, if x_9 were rich, then x_9 is a lawyer via universal biconditional elimination. From the fact that there is at least one x_9 for which x_9 is rich or x_9 will not play squash we can infer that there is at least one x_9 for which if x_9 plays squash, then x_9 is rich via existential rewriting. Finally, from the fact that there is at least one x_9 for which if x_9 plays squash, then x_9 is rich, and that for all x_9, if x_9 were rich, then x_9 is a lawyer we can infer that there is at least one x_9 for which if x_9 plays squash, then x_9 is a lawyer via existential transitivity. Therefore, the answer is yes.