Consider the following premises. For all x_8, x_8 will take a plane or x_8 will play squash. For all x_8, x_8 will not play squash or x_8 is a taxi driver. There is at least one x_8 for which x_8 will not take a plane. Can we infer the following from them? If we can, name the inference rule being used: There is at least one x_8 for which x_8 will write a letter or x_8 is a taxi driver.
 From the fact that for all x_8, x_8 will take a plane or x_8 will play squash, and that there is at least one x_8 for which x_8 will not take a plane we can infer that there is at least one x_8 for which x_8 will play squash via existential disjunctive syllogism. From the fact that there is at least one x_8 for which x_8 will play squash we can infer that there is at least one x_8 for which x_8 will play squash or x_8 will write a letter via existential addition. Finally, from the fact that there is at least one x_8 for which x_8 will play squash or x_8 will write a letter, and that for all x_8, x_8 will not play squash or x_8 is a taxi driver we can infer that there is at least one x_8 for which x_8 will write a letter or x_8 is a taxi driver via existential resolution. Therefore, the answer is yes.