One cases of books weight 35 pounds. one case of magazines weights 23 pounds. a book store wants to ship 72 cases of books and 94 cases of magazines to another store. what is the total weight of the shipment

Ascientist wants to use a model to present the results of his detailed scientific investigation. why would a model be useful? a )because the model makes the concepts easier to understand b) because the model is easy to put together and to use c) because the model prevents other scientists from asking questions d) because the model requires the audience to pay full attention to it i don't know what to choose because between a and d a is much more likely than d because it only wants to get the attention of the audience. i'm confuse.