Consider the following premises. For all x_8, x_8 is a nurse if and only if x_8 is curious. For all x_8, if x_8 climbs a mountain, then x_8 is a nurse. There is at least one x_8 for which x_8 is a taxi driver. For all x_8, x_8 will climb a mountain or x_8 is curious. 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 is a nurse and x_8 is a taxi driver.
 From the fact that for all x_8, x_8 is a nurse if and only if x_8 is curious we can infer that for all x_8, if x_8 were curious, then x_8 is a nurse via universal biconditional elimination. From the fact that for all x_8, if x_8 climbs a mountain, then x_8 is a nurse, that for all x_8, if x_8 were curious, then x_8 is a nurse, and that for all x_8, x_8 will climb a mountain or x_8 is curious we can infer that for all x_8, x_8 is a nurse via universal disjunction elimination. Finally, from the fact that for all x_8, x_8 is a nurse, and that there is at least one x_8 for which x_8 is a taxi driver we can infer that there is at least one x_8 for which x_8 is a nurse and x_8 is a taxi driver via existential conjunction. Therefore, the answer is yes.