cm typically refers to the unit of measurement, a Centimeter -- 100 Centimeters = 1 Meter, 1 Centimeter = .394 Inches
210 (7x6x5)
0.2911 cm
You use a ruler or similar object that is marked with centimeters. If your ruler only has inches, measure the inches, then multiply with 2.54 to get centimeters.
Divide millimeters by 10: 56 millimeters is 5.6 centimeters.
a postage stamp.
[object Object]
you'll need lots of centimeters to go in a 56 millimeter object
210 (7x6x5)
520 centimeters.
a thumb tack is about 2 centimeters long.
0.2911cm
just measure it in centimeters
0.2911 centimeter
0.2911 cm
12 cm
you measure the thickness of a book in inches.
If an object weights 50mm its will be 5 centimetres