Stephan says that the numbers 38 and 40 are relatively prime. Explain why he is incorrect in making this statement

After two years, how much has been paid into interest?

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.

700 miles the train takes 5 hours to a travel the distance at what unit rate is the train traveling?