Consider the following premises. James is a lawyer. David is a cashier if and only if Richard is a bartender. If Karen goes running, then James is not a lawyer. Richard is a bartender if and only if Karen is running. Can we infer the following from them? David is not a cashier.
 From the fact that if Karen goes running, then James is not a lawyer, and that James is a lawyer we can infer that Karen is not running. From the fact that Richard is a bartender if and only if Karen is running, and that Karen is not running we can infer that Richard is not a bartender. Finally, from the fact that David is a cashier if and only if Richard is a bartender, and that Richard is not a bartender we can infer that David is not a cashier. Therefore, the answer is yes.