In mathematics, especially in set theory, a setA is a subset of a set B, or equivalently B is a superset of A, if A is "contained" inside B, that is, all elements of A are also elements of B. A and B may coincide. The relationship of one set being a subset of another is called inclusion or sometimes containment.
Asbestos (pronounced , or ) is a set of six naturally occurring silicate minerals, which all have in common their eponymousasbestiformhabit: long (roughly 1:20 aspect ratio), thin fibrous, with each visible fiber composed of millions of microscopic "fibrils" that can be released by abrasion and other processes. They are commonly known by their colors, as blue asbestos, brown asbestos, white asbestos, and green asbestos.
Rodents are of the orderRodentia, characterised by a single pair of continuously growing incisors in each of the upper and lower jaws that must be kept short by gnawing.