1) The concept of campaign finance refers to the funding and financial resources required to support political campaigns, including donations from individuals, organizations, and political action committees (PACs).

2) Oceans play a crucial role in regulating the Earth's climate by absorbing and storing large amounts of heat and carbon dioxide.

3) Democracy is a system of government in which power is vested in the people, who exercise it through elected representatives. It allows for political participation, freedom of speech, and protection of individual rights and liberties.

4) The book series "The Chronicles of Narnia" by C.S. Lewis has sold over 100 million copies worldwide.