Consider the following premises. There is at least one x_2 for which if x_2 were an office clerk, then x_2 is an electrician. For all x_2, if x_2 were rich, then x_2 is an office clerk. For all x_2, if x_2 were an electrician, then x_2 is rich. Can we infer the following from them? For all x_2, if is not true that x_2 is rich if and only if x_2 is an electrician.
 From the fact that for all x_2, if x_2 were rich, then x_2 is an office clerk, and that there is at least one x_2 for which if x_2 were an office clerk, then x_2 is an electrician we can infer that there is at least one x_2 for which if x_2 were rich, then x_2 is an electrician. Finally, from the fact that there is at least one x_2 for which if x_2 were rich, then x_2 is an electrician, and that for all x_2, if x_2 were an electrician, then x_2 is rich we can infer that there is at least one x_2 for which x_2 is rich if and only if x_2 is an electrician, which contradicts that For all x_2, if is not true that x_2 is rich if and only if x_2 is an electrician. Therefore, the answer is no.