They are not related. Each is an independent healthcare company. HCA primarily operates hospitals and LCA (a/k/a LabCorp) primarily provides laboratory testing services to physicians.
The United States is a republic in North America. It shares a border with Canada, the Atlantic Ocean, the Pacific Ocean and Mexico.
Canada, Mexico, and South America
the thin peice of land between north and south America
There have been many different locations from Washington DC to rural Washington state.