Secretive and wary, weasels are difficult to study in. nature, and many gaps remain in our knowledge of their. reproduction. Two of the species covered in this Wild-. life Note (the ermine and the long-tailed weasel) exhibit.
Extensive - Properties that do depend on the amount of matter present. Mass - A measurement of the amount of matter in a object (grams). Weight - A measurement of the gravitational force of attraction of the earth acting on an object. Volume - A measurement of the amount of space a substance occupies. Length.
The density of a substance is the relationship between the mass of the substance and how much space it takes up (volume). Density equals the mass of the substance divided by its volume; D = m/v. Objects with the same volume but different mass have different densities. Density is defined as mass per unit volume.