Consider the following premises. John is curious. If it is overcast, then John is not curious. For all x, x will make tea. Can we infer the following from them? If we can, name the inference rule being used: It is overcast.
 From the fact that for all x, x will make tea we can infer that David is making tea via universal instantiation. Finally, from the fact that if it is overcast, then John is not curious, and that John is curious we can infer that it is not overcast via modus tollens, which contradicts that It is overcast. Therefore, the answer is no.