What is the radius of the larger circle

Derricks dog sitting and darlene's dog sitting are competing for new business. the companies ran the ads shown. which dog sitting service is more economic to use if you need 5 hours of service? explain.

The line y = x + passes through (−3, 7) and is parallel to y = 4x − 1.

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.