Centimeter: Centimeter is the unit of length measurement, which is equal to one hundredth of one meter. The English symbol is abbreviated as cm. 1cm =1100m =1cm (cm) =10mm (mm) = 0.1DM (decimeter) = 0.0/kloc-0.

Meter: meter is the basic unit of length in the international system of units, with the symbol m, and one meter is equal to 10 decimeter. It can be used to measure length, width and height.

Basic line segment: refers to the limited part between two points on a straight line (including two endpoints), which is represented by letters A, B or lowercase letters representing its two endpoints. Sometimes these letters also represent the length of the line segment, which is recorded as line segment AB or line segment BA, line segment A .. where A and B represent the two endpoints of the line segment.

Line segment properties:

The length of (1) line segment is limited and can be measured.

(2) A line segment has two endpoints.

(3) The line segment has symmetry.

(4) The straight line between two points is the shortest distance between them.

(5) Of all the straight lines connecting two points, the line segment is the shortest. It is called the shortest line segment between two points.

(6) The sum of two sides of a triangle is greater than the third side.