21. Both were designed to run along a contour line . 22. Contour lines are curves that connect contiguous points of the same altitude ( isohypse ).23. In economics, contour lines can be used to describe features which vary quantitatively over space. 24. Depth contour lines show the shape of underwater relief. 25. Except for minor irregularities caused by erosion, any contour line drawn is practically a circle. 26. Positive values denote westerly winds and the contour line is at 0 m / s. 27. Meteorological contour lines are based on generalization from the point data received from weather stations. 28. Black " ink " outlines and contour lines can be created using a variety of methods. 29. The result is that the object is drawn with a black outline and interior contour lines . 30. It combines surface maps with topographical maps, which represent changes in the terrain with contour lines .
