1) The United States recently held its presidential election in 2020, resulting in Joe Biden being elected as the 46th President of the United States and Kamala Harris as the Vice President, making history as the first female Vice President.

2) The world's most expensive car is the Bugatti La Voiture Noire, which sold for over $18 million.

3) Mountains are formed through various geological processes, including tectonic plate movements, volcanic activity, and erosion.

4) The invention of the transistor by Bell Laboratories in 1947 revolutionized electronics and paved the way for the development of smaller, more efficient electronic devices.