It is often called a straight-edge.
use a yard stick
Use a tape measure!
It could be a ruler. Just a number line.
It depends on your ruler and what units are on your ruler. To measure to the nearest inch just find the inch measurement and round up or down to get to the nearest inch in your measurement is between two whole numbers.
i think you can use a ruler not sure
It could be called a straight edge.
A ruler with no numbers is often referred to as a "blank ruler" or a "non-standard ruler." It can be used for drawing straight lines or measuring lengths based on visual estimation or other reference points, rather than numerical measurements. This type of ruler is useful in artistic contexts or for educational purposes, allowing users to focus on spatial relationships without the distraction of numerical values.
2.5cm
by the numbers that are marked there
The numbers are to the left of the inch markers.
Stright edge
They both have numbers.
inches, centimeters and millimeters
A length of two units!
"Communist ruler" is contradiction in terms, since communism, by definition, is without government.
The one with shorter distances between the numbers.
use a ruler