I will say there will be 375 white lines. Each line is 3 meters long, with a 5 meter gap. This would give us a space of 8 meters from the beginning of one white line to the beginning of the next. If we divide 3000 meters (3 km) by 8 meters, we get 375. So, the first white line would start at the beginning of the 3 km. The end of the 3 km space would be marked by the very beginning of the 376th white line
You swim over the line.
A ruler
definition: marked with lines, especially parallel lengthwise lines; striped
NO
There is no official set of "lines". Some globes and maps have more lines, spaced closer together. Some globes and maps have fewer lines, spaced farther apart. Some globes and maps have no lines at all. We have no way of knowing how many latitudes and longitudes are marked on the map that you're looking at today, and the next one you see may be marked at a different interval.
with broken white lines
Contour lines connect points of equal height, and show grades of hills, the closer together the lines the steeper the grade. The map legend should tell you the difference in elevation between lines, this could be in feet or meters
Flagging is used to mark property lines. In wooded areas, the closest tree is marked. Surveyors use various techniques to mark trees to indicate property lines.
latitude
3 meters
A contour interval shows a change in elevation on a topographical map. If the contour interval is 20 then the elevation change between two contour lines is 20 meters
By vertical lines, like meridians, but not always straight.