The line would have to pass through at least two points.
Answer:
For the countour part: Map c, contour is 50m (the lines increases/decreases with 50 meters each step). Map b, need to see the whole map to decide.
The entire United States and the rest of the world serve as the hinterland for all of the following cities except Tucson.
The answer is - Sunspots.
Sunspots are dark in appearance, but only on a visible light, and this is due to the fact that they are much cooler than the surrounding areas, but that doesn't mean by any means that the sunspots are cool, on contrary, they are very hot too. Sunspots actually are storms that appear in the lower atmosphere of the sun.
