Consider the following premises. If David were excited, then Thomas is not an office clerk. Thomas is an office clerk and it is late. If David were not excited, then it is windy. If Richard sleeps, then it is windy. Can we infer the following from them? If we can, name the inference rule being used: It is not windy.
 From the fact that Thomas is an office clerk and it is late we can infer that Thomas is an office clerk via simplification. From the fact that if David were excited, then Thomas is not an office clerk, and that Thomas is an office clerk we can infer that David is not excited via modus tollens. From the fact that David is not excited we can infer that David is not excited or Richard is sleeping via addition. Finally, from the fact that if David were not excited, then it is windy, that if Richard sleeps, then it is windy, and that David is not excited or Richard is sleeping we can infer that it is windy via disjunction elimination, which contradicts that It is not windy. Therefore, the answer is no.