instruction:
In this task you will be given an answer to a question. You need to generate a question. The answer given should be a correct answer for the generated question.
question:
An autotroph ('self-feeding', from the Greek autos 'self' and trophe 'nourishing') or producer, is an organism that produces complex organic compounds (such as carbohydrates, fats, and proteins) from simple substances present in its surroundings, generally using energy from light (photosynthesis) or inorganic chemical reactions (chemosynthesis). They are the producers in a food chain, such as plants on land or algae in water (in contrast to heterotrophs as consumers of autotrophs). They do not need a living source of energy or organic carbon. Autotrophs can reduce carbon dioxide to make organic compounds for biosynthesis and also create a store of chemical energy. Most autotrophs use water as the reducing agent, but some can use other hydrogen compounds such as hydrogen sulfide. Some autotrophs, such as green plants and algae, are phototrophs, meaning that they convert electromagnetic energy from sunlight into chemical energy in the form of reduced carbon.
answer:
what is the meaning of autotrophs in science


question:
In 1681, in partial repayment of a debt, Charles II of England granted Penn a charter for what would become the Pennsylvania colony. Despite the royal charter, Penn bought the land from the local Lenape to be on good terms with the Native Americans and ensure peace for his colony. Penn made a treaty of friendship with Lenape chief Tammany under an elm tree at Shackamaxon, in what is now the city's Fishtown neighborhood. Penn named the city Philadelphia, which is Greek for brotherly love (from philos, 'love' or 'friendship', and adelphos, 'brother'). As a Quaker, Penn had experienced religious persecution and wanted his colony to be a place where anyone could worship freely. This tolerance, far more than afforded by most other colonies, led to better relations with the local native tribes and fostered Philadelphia's rapid growth into America's most important city.
answer:
why philadelphia called the city of brotherly love


question:
The Chesapeake Bay Bridge -- Tunnel (CBBT) is a 23-mile (37 km) fixed link crossing at the mouth of the Chesapeake Bay in the U.S. state of Virginia. It connects Northampton County on the Delmarva Peninsula with Virginia Beach, which is part of the Hampton Roads metropolitan area. The bridge -- tunnel originally combined 12 miles (19 km) of trestle, two 1-mile-long (1.6 km) tunnels, four artificial islands, four high-level bridges, approximately 2 miles (3.2 km) of causeway, and 5.5 miles (8.9 km) of approach roads -- crossing the Chesapeake Bay and preserving traffic on the Thimble Shoals and Chesapeake shipping channels. It replaced vehicle ferry services that operated from South Hampton Roads and from the Virginia Peninsula from the 1930s. Financed by toll revenue bonds, the bridge -- tunnel was opened on April 15, 1964, and remains one of only ten bridge -- tunnel systems in the world, three of which are located in Hampton Roads, Virginia.
answer:

when was the chesapeake bay bridge tunnel completed


