<em>it must be a compound as it is the combination of some materials ..it is not important for a compound to must have three materials ..they may be more or less .. as there are further classifications of compound .. also sometimes it may be a molecule depending upon the elements of which it is made ..</em>
6 or 7
A child's 20 baby teeth, which often come in by age 3, usually fall out in the same order they came in. That means the lower center teeth (lower center incisors) are usually the first to go, around age 6 or 7. The top center pair is next.
