Copies at the local library cost $0.15 each. a new cooler costs $200 and it costs $0.02 to make a copy. how many copies would have to be made for the cost of making your own copies to be equal to the cost of copying at the library

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.

Anyone? 15m is what percent of 60m; 3m; 30m; 1.5 km?

In the diagram of circle o, what is the measure of zabc?