Consider the following premises. If it snows, then Joseph is poor. If Joseph were poor, then Karen is playing tennis. If Karen plays tennis, then it is snowing. For all z_1, z_1 will not play tennis. Can we infer the following from them? If we can, name the inference rule being used: Joseph is poor.
 From the fact that for all z_1, z_1 will not play tennis we can infer that Karen is not playing tennis via universal instantiation. From the fact that if Karen plays tennis, then it is snowing, and that if it snows, then Joseph is poor we can infer that if Karen plays tennis, then Joseph is poor via transitivity. From the fact that if Joseph were poor, then Karen is playing tennis, and that if Karen plays tennis, then Joseph is poor we can infer that Joseph is poor if and only if Karen is playing tennis via biconditional introduction. Finally, from the fact that Joseph is poor if and only if Karen is playing tennis, and that Karen is not playing tennis we can infer that Joseph is not poor via biconditional elimination, which contradicts that Joseph is poor. Therefore, the answer is no.