Answer:
take notes on important details
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.
The secret service, which is a federal policing agency that was part of the department of Treasury. At least until 2003, when is became the department of Homeland Security.
B. That is the key objective.
