Consider the following premises. Jennifer is not a soldier. Jennifer is a soldier if and only if Barbara is playing tennis. Barbara is playing tennis if and only if Charles is a cashier. For all x, if x makes tea, then x is a cashier. Can we infer the following from them? If we can, name the inference rule being used: Charles is making tea.
 From the fact that for all x, if x makes tea, then x is a cashier we can infer that if Charles makes tea, then Charles is a cashier via universal instantiation. From the fact that Jennifer is a soldier if and only if Barbara is playing tennis, and that Jennifer is not a soldier we can infer that Barbara is not playing tennis via biconditional elimination. From the fact that Barbara is playing tennis if and only if Charles is a cashier, and that Barbara is not playing tennis we can infer that Charles is not a cashier via biconditional elimination. Finally, from the fact that if Charles makes tea, then Charles is a cashier, and that Charles is not a cashier we can infer that Charles is not making tea via modus tollens, which contradicts that Charles is making tea. Therefore, the answer is no.