👉 Densities are mathematical quantities that describe how much a quantity (such as mass, volume, or energy) occupies space. They are fundamental to many physical and engineering applications in science, engineering, and economics. In simple terms, densities represent the amount of matter per unit volume. For example, if you have a cube with sides measuring 1 meter long, its volume would be: \[ V = \text{length}^3 = (1m)^3 = 1\,m