Earthquakes in New Zealand occur because we are located on the boundary of two of the world's major tectonic plates – the Pacific Plate and the Australian Plate. These plates are colliding with huge force, causing one to slowly grind over, under or alongside the other.
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 world of heaven in my opinion