1) The concept of proportional representation, used in some electoral systems, aims to ensure that political parties' representation in government aligns more closely with the proportion of votes they receive from the electorate.

2) The Civil Rights Act of 1964 in the United States outlawed discrimination based on race, color, religion, sex, or national origin.

3) Mountains are important water sources, as they capture and store precipitation, feeding rivers and supporting ecosystems downstream.

4) A group of flamingos is called a "flamboyance."