Given the hints in the question.
a.) The x-coordinate is the elevation in meters.
b.) The y-coordinate is the tempature in °C.
A city above sea level must have a positive elevation.
Therefore, the quadrants that we should look after must be the quadrants that have positive x-coordinates.
Quadrant I and IV are the only quadrants in the graph that have positive x-coordinates. Therefore, points that could be seen in these quadrants shows cities that are above sea level.
