The smallest measurement unit on a typical ruler is usually 1 millimeter (mm). A millimeter is one-tenth of a centimeter, and most rulers have small marks between the centimeters to show these millimeters. These tiny divisions help measure objects more accurately, especially when the length is smaller than a centimeter. For example, if you’re measuring something like the width of a pencil, the millimeter markings on the ruler allow for precise measurements.

This question related to Chapter 5 Science Curiosity Class 6th NCERT.
From the Chapter 5. Measurement of Length and Motion.
Give answer according to your understanding.