Lea and valentine each started a puppy business. because valentine is older, she charges a starting fee of $2.5 and $5 for every hour she babysits. iris charges a flat fee of $6 and charges $4 per hour. ms. kaylie wanted to ee which rate was better but found that the rates could be the same. at what hour will she pay the same amount? use x to represent hours

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.