1) Rihanna, born Robyn Rihanna Fenty, is a Barbadian singer, actress, and businesswoman. She has achieved great success in the music industry with hits like "Umbrella," "Diamonds," and "Work," and has also ventured into the worlds of fashion and cosmetics with her brands.

2) The first commercial GPS (Global Positioning System) was launched in 1989 and provided accurate positioning and navigation capabilities to users worldwide.

3) The eye of a cyclone is a region of calm, relatively clear skies and light winds at the center of the storm.

4) Mount Everest, located in the Himalayas, is the highest mountain on Earth, reaching a peak elevation of 29,032 feet (8,848 meters).