Consider the following premises. It is not snowing. It is late or Robert is a bartender. Robert is a bartender if and only if it is snowing. It is not late or James is a mechanic. Can we infer the following from them? If we can, name the inference rule being used: James is not a mechanic.
 From the fact that it is late or Robert is a bartender, and that it is not late or James is a mechanic we can infer that Robert is a bartender or James is a mechanic via resolution. From the fact that Robert is a bartender if and only if it is snowing, and that it is not snowing we can infer that Robert is not a bartender via biconditional elimination. Finally, from the fact that Robert is a bartender or James is a mechanic, and that Robert is not a bartender we can infer that James is a mechanic via disjunctive syllogism, which contradicts that James is not a mechanic. Therefore, the answer is no.