Consider the following premises. For all x_10, if x_10 plays squash, then x_10 is a mechanic. There is at least one x_10 for which if x_10 sleeps, then x_10 is playing squash. For all x_10, if x_10 were a doctor, then x_10 is playing squash. For all x_10, x_10 will sleep or x_10 is a doctor. For all x_10, if x_10 plays tennis, then x_10 is a mechanic. Can we infer the following from them? There is at least one x_10 for which x_10 is a mechanic.
 From the fact that there is at least one x_10 for which if x_10 sleeps, then x_10 is playing squash, that for all x_10, if x_10 were a doctor, then x_10 is playing squash, and that for all x_10, x_10 will sleep or x_10 is a doctor we can infer that there is at least one x_10 for which x_10 will play squash. From the fact that there is at least one x_10 for which x_10 will play squash we can infer that there is at least one x_10 for which x_10 will play squash or x_10 will play tennis. Finally, from the fact that for all x_10, if x_10 plays squash, then x_10 is a mechanic, that for all x_10, if x_10 plays tennis, then x_10 is a mechanic, and that there is at least one x_10 for which x_10 will play squash or x_10 will play tennis we can infer that there is at least one x_10 for which x_10 is a mechanic. Therefore, the answer is yes.