Questions

The nucleus of an atom is the densest part of an atom. It contains the protons and neutrons of an atom.

A candidate key is a column, or set of columns, in a table that can uniquely identify any database record without referring to any other data. Each table may have one or more candidate keys, but one candidate key is unique, and it is called the primary key.

The Cold War started with building tensions between the US and the USSR during World War II. As Stalin began to annex more countries and spread communism throughout Eastern Europe, the US began to feel threatened and feared that they would start a war amongst the capitalist nations. The US started an attempt to limit the spread of communism and protect capitalism, which led to a series of passive aggressive and indirectly hostile exchanges between the two nations.

The beginning of the end of the cold war, the Berlin Wall came down. The USSR began to collapse the following year, in 1990.

All atoms of an element have the same number of protons. The number of protons in an element is a primary identifier known as its atomic number. The number of electrons is the same as the number of protons.