Consider the following premises. For all x_29, x_29 will climb a mountain. James is not taking a plane. James is taking a plane or Thomas is writing a letter. Can we infer the following from them? If we can, name the inference rule being used: Elisabeth is climbing a mountain or Thomas is reading a book.
 From the fact that for all x_29, x_29 will climb a mountain we can infer that Elisabeth is climbing a mountain via universal instantiation. From the fact that James is taking a plane or Thomas is writing a letter, and that James is not taking a plane we can infer that Thomas is writing a letter via disjunctive syllogism. From the fact that Elisabeth is climbing a mountain, and that Thomas is writing a letter we can infer that Elisabeth is climbing a mountain and Thomas is writing a letter via conjunction. From the fact that Elisabeth is climbing a mountain and Thomas is writing a letter we can infer that Elisabeth is climbing a mountain via simplification. Finally, from the fact that Elisabeth is climbing a mountain we can infer that Elisabeth is climbing a mountain or Thomas is reading a book via addition. Therefore, the answer is yes.