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.
2.5cm
by the numbers that are marked there
Stright edge
The numbers are to the left of the inch markers.
inches, centimeters and millimeters
A length of two units!
They both have numbers.
"Communist ruler" is contradiction in terms, since communism, by definition, is without government.
The one with shorter distances between the numbers.
use a ruler
Probably centimetres.