Rodrigo and Jannes are filling a swimming pool with water. Rodrigo’s hose can fill the pool twice as fast as Jannes’ hose. If it takes 5 hours to fill the pool, how long would it take Rodrigo to fill the pool alone?

What is the standard deviation of the following data set rounded to the nearest tenth? 3, 17, 18, 15, 12, 21, 9

What is the fewest number of full weeks briyana would have to work to have enough money? 8 weeks9 weeks 10 weeks11 weeks

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.