scopeeconomics

A pipe needs space below ground. You are defining that space before it becomes excavation, disposal and installation cost.
Water-main renewalPlace each label on the correct part of the trench.
A section is one slice through the work. On site, that section continues along the installed alignment.

Select a marker to connect the physical work to the estimate.
Tomas Castelazo · CC BY-SA 3.0 · resized; numbered markers added.
Source: https://commons.wikimedia.org/wiki/File:114_inch_pipe_installation.jpg
Licence: https://creativecommons.org/licenses/by-sa/3.0/

Illustrative scene. Use the lesson figures and records for measurements.
Drag a label, or select a label then a region. Select a placed label to move it before checking.