Consider the following premises. There is at least one x_6 for which x_6 will drink water. For all x_6, if x_6 were a doctor, then x_6 is a mechanic. For all x_6, if x_6 were a musician, then x_6 is a mechanic. For all x_6, if x_6 drinks water, then x_6 is a musician. Can we infer the following from them? There is at least one x_6 for which x_6 is a mechanic.
 From the fact that for all x_6, if x_6 drinks water, then x_6 is a musician, and that there is at least one x_6 for which x_6 will drink water we can infer that there is at least one x_6 for which x_6 is a musician. From the fact that there is at least one x_6 for which x_6 is a musician we can infer that there is at least one x_6 for which x_6 is a musician or x_6 is a doctor. Finally, from the fact that for all x_6, if x_6 were a musician, then x_6 is a mechanic, that for all x_6, if x_6 were a doctor, then x_6 is a mechanic, and that there is at least one x_6 for which x_6 is a musician or x_6 is a doctor we can infer that there is at least one x_6 for which x_6 is a mechanic. Therefore, the answer is yes.