The three principles that describe how the economy as a whole works are: (1) a country's standard of living depends on its ability to produce goods and services; (2) prices rise when the government prints too much money; and (3) society faces a short-run tradeoff between inflation and unemployment.
Silicon dioxide is dissolvable in water and has a high melting point because the atoms in the dioxide has a strong bond between them, which requires a lot of energy to break them.
In history such as World History? You should be able to distinguish the trends and differences in different periods say "Period 1 vs. Period 2" where each period represents a different range of years (in AP World History I learned it with 6 periods but it varies from year to year of when it is taught)
