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

2) The Iguazu Falls, located on the border between Argentina and Brazil, is a majestic waterfall system consisting of numerous cascades and islets. It is a UNESCO World Heritage site and one of the most impressive natural wonders in the world, attracting millions of visitors each year.

3) The Amazon rainforest produces more than 20% of the world's oxygen.

4) The Earth's core is primarily composed of iron and nickel and is as hot as the surface of the sun.