Final answer:
A line representing the bottom of the wall cabinets would normally be drawn 54 inches from the floor, maintaining an 18-inch clearance above the standard kitchen countertop height.
Step-by-step explanation:
When measuring up from the floor's high point, a line representing the bottom of the wall cabinets would typically be drawn at 54 inches (137 cm) from the floor. This standard height ensures that there is enough space between the countertop and the bottom of the wall cabinet, which is generally 18 inches (45.7 cm), as most kitchen countertops are around 36 inches (91.4 cm) high from the floor.
To find the height of a wall cabinet from the high point of the floor, a measuring tool such as a tape measure would be used. For example, if someone has a mirror with the top 1.715 m from the floor and the bottom 0.825 m from the floor, the height of the mirror would be the difference between these two values, which is 0.890 m.
This process of measuring the difference in height is similar to how you would measure the height with a U tube, by finding the difference between the two levels of mercury.