Depression
Called both Elevation Lines or Contour Lines
Closed circles on a topographic map represent contour lines that indicate a hill or a mountain. The innermost circle typically signifies the highest point of elevation, with elevation decreasing as one moves outward. If the closed circle has hachures (small lines) pointing inward, it represents a depression or a bowl-shaped area instead.
The contours of the water table lines are the same as the contours of other topographical lines. The only indication of water tables might be elevation lines but they are not unique to water tables.
A topographical map will show contour lines and spot heights, with mountain tops marked with their height.
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A closed circle with short lines inside on a topographical map typically represents a depression or a sinkhole. The short lines, known as hachures, indicate the slope of the terrain, with the lines pointing towards the lower elevation to show that the area is lower than the surrounding land. This symbol helps map users quickly identify areas of lower elevation within a generally elevated landscape.
A circle has infinite lines of symmetry caused by its diameter which can be rotated inside the circle.
An open circle should have a dashed circumference, a closed circle a solid one.
Topographical lines
There are infinite lines of symmetry in a circle because its diameter can revolve inside it at any position.
Draw two diameter lines, then draw a circle inside the circle.
A fraction.
The circles are called contour lines. A contour line connects points of the same elevation. When the lines are close together on a map that show the land is steep.
Four.
Called both Elevation Lines or Contour Lines
a circle with three radius lines
revelation