Quetstion 4 is A The other question is B
The correct answer is the editorial page :)
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.
Confucianism emerged as a philosophy of social conduct rather than as a belief in one or more deities.
C. Bismarck used a series of wars and political incidents to raise nationalistic feelings and install political leaders he could manipulate