How do I solve this word problem?

How many square feet of out door carpet will we need for this hole? 8ft 3ft 12ft 4ft

Reflect the point (7,0) across the y-axis

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.