In order to know the answer for this one, let us analyze the whole problem.
Given that the store already lose $100 stolen by the guy, this guy also bought a merchandise worth 70$, and gets a change of $30. The merchandise was paid, but still, the store lost $100, and then an additional $30, for giving it back to the guy. So the total lost of the store would be $130. Hope this answer helps.
Answer:
10 miles in 75 minutes
Step-by-step explanation:
Knowing that a straight line is 180° you can use this to your advantage. If you take all parts of the ratio and add them together you can get the total number of "pieces" the 180° will be divided into.

Then divide the 180° by the total.

Now you can use the value for one "piece" and multiply it by how ever many the ratio says.
The angle FOG has the 4 value of the ratio so you multiply 20 by 4 to get the value of the angle.

m<FOG = 80°