- Gas Works Park (Wikipedia)
Gas Works Park is a park located in Seattle, Washington, United States. It is a 19.1-acre (77,000 m2) public park on the site of the former Seattle Gas Light Company gasification plant, located on the north shore of Lake Union at the south end of the Wallingford neighborhood. The park was added to the National Register of Historic Places on January 2, 2013, over a decade after being nominated.
- Tetrahedron (Wikipedia)
In geometry, a tetrahedron (pl.: tetrahedra or tetrahedrons), also known as a triangular pyramid, is a polyhedron composed of four triangular faces, six straight edges, and four vertices. The tetrahedron is the simplest of all the ordinary convex polyhedra.
