Q:Information: - High-speed rail is a type of rail transport that operates significantly faster than traditional rail traffic, using an integrated system of specialized rolling stock and dedicated tracks. While there is no single standard that applies worldwide, new lines in excess of and existing lines in excess of are widely considered to be high-speed, with some extending the definition to include lower speeds in areas for which these speeds still represent significant improvements. The first such system began operations in Japan in 1964 and was widely known as the bullet train. High-speed trains normally operate on standard gauge tracks of continuously welded rail on grade-separated right-of-way that incorporates a large turning radius in its design. - Jackson (formerly, Botilleas, Botilleas Spring, Bottileas, Bottle Spring, and Botellas) is the county seat of Amador County, California. The population was 4,651 at the 2010 census, up from 3,989 at the 2000 census. The city is accessible by both State Route 49 and State Route 88. - George Stephenson (9 June 1781 12 August 1848) was an English civil engineer and mechanical engineer who built the first public inter-city railway line in the world to use steam locomotives, the Liverpool and Manchester Railway which opened in 1830. Renowned as the "Father of Railways", the Victorians considered him a great example of diligent application and thirst for improvement, with self-help advocate Samuel Smiles particularly praising his achievements. His rail gauge of , sometimes called "Stephenson gauge", is the standard gauge by name and by convention for most of the world's railways. - A census is the procedure of systematically acquiring and recording information about the members of a given population. It is a regularly occurring and official count of a particular population. The term is used mostly in connection with national population and housing censuses; other common censuses include agriculture, business, and traffic censuses. The United Nations defines the essential features of population and housing censuses as "individual enumeration, universality within a defined territory, simultaneity and defined periodicity", and recommends that population censuses be taken at least every 10 years. United Nations recommendations also cover census topics to be collected, official definitions, classifications and other useful information to co-ordinate international practice. - Amador County, officially the County of Amador, is a county in the U.S. state of California, in the Sierra Nevada. As of the 2010 census, the population was 38,091. The county seat is Jackson. - In rail transport, track gauge is the spacing of the rails on a railway track and is measured between the inner faces of the load-bearing rails. - A county seat is an administrative center, seat of government, or capital city of a county or civil parish. The term is used in the United States, Canada, Romania, China and Taiwan. In the United Kingdom and Ireland, county towns have a similar function. - The standard gauge (also Stephenson gauge after George Stephenson, International gauge, or normal gauge) is a widely used railway track gauge. Approximately 55% of the lines in the world are this gauge. All high-speed rail lines (except those in Russia, Uzbekistan, and Finland) are standard gauge. The distance between the inside edges of the rails is defined to be (except in the United States, where it is still defined in Imperial and US customary units as ). It is also called the UIC gauge or UIC track gauge, the European gauge in the EU and Russia, or uniform gauge in Queensland, Australia. - The Amador Central Railroad ( reporting mark AMC ) is a standard gauge railroad that operated 11.8 miles ( 19.0 km ) between a connection with the Southern Pacific Company ( SP ) at Ione and Martell near the town of Jackson , California . The carrier served the Sierra Nevada Foothills gold mining communities and hauled lumber products from the El Dorado National Forest . Amador is the name of the county in which the railroad operated . Given the information, choose the subject and object entities that have the relation of 'instance of'.
A:
amador central railroad , railway line