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) A newborn kangaroo is about 1 inch (2.5 centimeters) long and weighs less than a gram.

3) The first commercial mobile phone, the Motorola DynaTAC 8000X, was released in 1983 and weighed nearly 2 pounds.

4) 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.