They belong to different units, "ml" is the abbreviation of milliliter, representing the unit of volume; "cm" is the abbreviation of centimeter, which is a common expression of length unit. There is no direct conversion relationship between the two.

Extended data:

The unit of length refers to the basic unit for measuring spatial distance, which is formulated by human beings to standardize the length. Its international unit is "meter" (symbol "m"), and commonly used units are millimeter (mm), centimeter (cm), decimeter (dm), kilometer (km), meter (m), micron (micron) and nanometer (nm). Length units play an important role in various fields.

Geometric measurement, also known as length measurement, is a science with relatively early start, rapid development and mature technology in China. China is a famous ancient civilization with splendid ancient civilization. Measurement and testing technology is an important part of this civilization. As a geometric quantity in measurement, it has a long history of development.

China began to have ivory rulers as early as Shang Dynasty, which were made by unified measurement, the first emperor of Qin Dynasty, and had the bud of interchangeability, which has been confirmed by the archer crossbow machine unearthed from the eighth wonder of the terracotta warriors and horses in the world. Around 1600, China began to develop length and time measurement. The basic unit of length measurement, namely geometric measurement, is the meter.

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