Consider the following premises. For all x_4, if x_4 plays tennis, then x_4 is not working. For all x_4, x_4 will play tennis if and only if x_4 will make tea. There is at least one x_4 for which x_4 will work. Can we infer the following from them? There is at least one x_4 for which x_4 will not make tea.
 From the fact that for all x_4, if x_4 plays tennis, then x_4 is not working, and that there is at least one x_4 for which x_4 will work we can infer that there is at least one x_4 for which x_4 will not play tennis. Finally, from the fact that for all x_4, x_4 will play tennis if and only if x_4 will make tea, and that there is at least one x_4 for which x_4 will not play tennis we can infer that there is at least one x_4 for which x_4 will not make tea. Therefore, the answer is yes.