- Ocean Beach is a beach on the west coast of San Francisco, California, United States, bordering the Pacific Ocean. It is adjacent to Golden Gate Park, the Richmond District, and the Sunset District. The Great Highway runs alongside the beach, and the Cliff House and the site of the former Sutro Baths sit at the northern end. The beach is a part of the Golden Gate National Recreation Area, which is administered by the National Park Service.
- Radius (Wikipedia)
In classical geometry, a radius (pl.: radii or radiuses) of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length. The name comes from the Latin radius, meaning ray but also the spoke of a chariot wheel. The typical abbreviation and mathematical variable name for radius is R or r. By extension, the diameter D is defined as twice the radius