A normal metric ruler!
An ordinary ruler.
A metric ruler
If the ruler only has inches and millimeters, just use the millimeters side. Remember, there are 10 millimeters in 1 centimeter.
A ruler is usually divided by: inches, centimeters, and millimeters.
Get a ruler marked in centimeters and millimeters, anywhere basic school or business supplies are sold.
A metric ruler is use to measure centimeter and millimeters.1 centimeter (cm) = 10 millimeters (mm) .
1cm(centimeter) = 10mm (millimeter) The calculation can be expressed: 26/10=2.6
The millimeters on a ruler are the tiny lines in between each centimeter
It is a linear length and as a ruler it is not round.
The first line, not the edge of the ruler.
A ruler ?
30 centimeters