Grab a ruler. Draw a 3 cm line. There you go!
Scroll down to related links and look at "Inches and centimeters in comparison".
On a typical metric ruler, the major divisions are centimeters, with smaller marks at intervals of 0.1 cm (1 mm), and a medium-sized mark at the halfway point between centimeters. So 0.2 cm or 2 mm is two of the smallest intervals on the ruler.
4 inches are 10.16 centimeters.
A ruler
Just like snow - with a ruler, in inches or centimeters
Here you find inch and centimeter rulers. Scroll down to related links and look at "Inches and centimeters in comparison".
You should get a ruler and start measuring things in your home that look like they'd be two centimeters.
The customary ruler uses both inches and centimeters.
It look like 1.93
where is .39 on a ruler
a 30cm ruler