Final answer:
Six-digit grid coordinates are found using a topographic map, which is required to locate the precise easting and northing values for a given spot elevation, such as elevation point 210. Without access to the specific map, accurate coordinates cannot be provided.
Step-by-step explanation:
The six-digit grid coordinates represent the precision location on a map and are used to pinpoint specific features such as spot elevations. To find the six-digit grid coordinates for any specific location, including spot elevation 210, we look for the easting and northing values that align with our point of interest. These values are derived from the gridded lines on a map, with eastings read first and northings read second.
For this particular task, without a provided map, it's impossible to provide exact grid coordinates for spot elevation 210. The coordinates are typically found using a topographic map by locating the elevation point and then reading the horizontal line (easting) to the nearest 100 meters, and the vertical line (northing) to the nearest 100 meters. From there, you would estimate to the nearest 10 meters to get the final three digits for both easting and northing.
Therefore, in order to provide an accurate six-digit grid coordinate for the spot elevation 210, a specific topographic map reference is required.