Consider the following premises. If Karen were not rich, then Elisabeth is working. For all x_14, x_14 is not a sailor. If Karen were rich, then Karen is a sailor. Can we infer the following from them? If we can, name the inference rule being used: Elisabeth is working.
 From the fact that for all x_14, x_14 is not a sailor we can infer that Karen is not a sailor via universal instantiation. From the fact that if Karen were rich, then Karen is a sailor, and that Karen is not a sailor we can infer that Karen is not rich via modus tollens. Finally, from the fact that if Karen were not rich, then Elisabeth is working, and that Karen is not rich we can infer that Elisabeth is working via modus ponens. Therefore, the answer is yes.