$ETH If you know something else about the level, say it.

• Level surface elevation = elevation of the reference point + reading

• Elevation of any point = level surface elevation – reading

• Reading on the device = level surface elevation - required elevation

( The reading is positive if the point whose elevation is to be found is below the line of sight, and the reading is negative if the point is above the line of sight )

• Sum of the occurrences - sum of the precedents = elevation of the last point - elevation of the first point

• Number of occurrences = number of precedents

• Slope percentage = (vertical difference / horizontal distance) * 100

• Comparison surface level: it is a continuous reference surface to which all point elevations are related, assuming its elevation equals zero (and it is usually the sea level)

• Point elevation: the amount of