Control Elevation Analysis

The task was to arrange the controls from the lowest to the highest.

First, we draw the index contours of each level using different colors.
The lowest index contour on the map is marked in blue, and the next one above it in light blue.
See Figure with mark "1".

In this task, it is easier to start determining the control elevations by identifying the highest controls first, because the top of the slope is easier to recognize on the map.
We can see that controls 3 and 2 are the highest, with control 3 higher than control 2.

Next, we distribute the remaining controls between the blue and light-blue index contours.
The lowest among them is control 9, as it is located just above the blue index contour.

Next comes control 4, and then control 1, followed by control 5, which is the highest of this group because it lies only one contour below the light-blue index contour.

The most challenging part of the task turned out to be the remaining controls, which are located below the blue index contour. See figure with mark "2".

Three controls are located below the blue index contour and above the form line (shown as a red line in the figure).
These are controls 7, 8, and 6.

Therefore, we can place an equality sign between them — based on the map, we cannot determine their exact relative elevation.\
Only one control, number 10, is located below the form line (marked in red in the figure), making it the lowest control on the entire map.
Therefore, the solution to the task can be written as follows (controls ordered by elevation, from lowest to highest):
10, 6 = 7 = 8, 9, 4, 1, 5, 2, 3.

Aleksandr Alekseyonok, January 15, 2026.

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