Answer:
For a war if I'm right. I think that was the beginning of the American Civil War. I could be wrong though.
Explanation:
I’m pretty sure B.
If I’m wrong someone else can give the answer.
Because it is important to know the composition of the object
Density is the ratio of the mass of a sample to the volume occupied by that mass, and expresses how much mass there is per unit volume of a given portion of matter. Density is a physical property of extreme importance in the characterization, identification and use of substances or materials.
