Consider the following premises. For all y_1, if y_1 were a server, then y_1 is drinking water. For all y_1, if y_1 were an office clerk, then y_1 is drinking water. For all y_1, y_1 is a musician or y_1 is a writer. For all y_1, y_1 is not a writer or y_1 is a server. For all y_1, if y_1 drinks water, then y_1 is an office clerk. For all y_1, y_1 is not a musician or y_1 is an office clerk. Can we infer the following from them? If we can, name the inference rule being used: For all y_1, y_1 will drink water.
 From the fact that for all y_1, y_1 is a musician or y_1 is a writer, and that for all y_1, y_1 is not a musician or y_1 is an office clerk we can infer that for all y_1, y_1 is a writer or y_1 is an office clerk via universal resolution. From the fact that for all y_1, if y_1 drinks water, then y_1 is an office clerk, and that for all y_1, if y_1 were an office clerk, then y_1 is drinking water we can infer that for all y_1, y_1 will drink water if and only if y_1 is an office clerk via universal biconditional introduction. From the fact that for all y_1, y_1 is a writer or y_1 is an office clerk, and that for all y_1, y_1 is not a writer or y_1 is a server we can infer that for all y_1, y_1 is an office clerk or y_1 is a server via universal resolution. From the fact that for all y_1, y_1 will drink water if and only if y_1 is an office clerk we can infer that for all y_1, if y_1 were an office clerk, then y_1 is drinking water via universal biconditional elimination. Finally, from the fact that for all y_1, if y_1 were an office clerk, then y_1 is drinking water, that for all y_1, if y_1 were a server, then y_1 is drinking water, and that for all y_1, y_1 is an office clerk or y_1 is a server we can infer that for all y_1, y_1 will drink water via universal disjunction elimination. Therefore, the answer is yes.