Generally speaking, when "square" is used as the unit of measurement, "cubic" is used, so 4000 cubic meters of water should be equal to 04000 cubic meters of water.

Cubic meter, pronounced as lì fāng mǐ, is the unit of volume, and the symbol m_ ((Unicode code for this word is 33A5)) is equal to the volume of a cube with a side length of one meter, which is equal to one cubic meter. It is an international unit of volume.

Water (chemical formula H_O) is an inorganic substance composed of two elements: hydrogen and oxygen. It is non-toxic and drinkable. At normal temperature and pressure, it is a colorless and odorless transparent liquid, which is called the source of human life and an important substance to maintain life, also called hydrogen oxide.