This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
--------
Question: The governments in Berlin, Bremen and Hamburg are designated by the term Senate. In the three free states of Bavaria, Saxony, and Thuringia the government is referred to as the State Government (Staatsregierung), and in the other ten states the term Land Government (Landesregierung) is used. Before January 1, 2000, Bavaria had a bicameral parliament, with a popularly elected Landtag, and a Senate made up of representatives of the state's major social and economic groups. The Senate was abolished following a referendum in 1998. The states of Berlin, Bremen, and Hamburg are governed slightly differently from the other states. In each of those cities, the executive branch consists of a Senate of approximately eight, selected by the state's parliament; the senators carry out duties equivalent to those of the ministers in the larger states. The equivalent of the Minister-President is the Senatspräsident (President of the Senate) in Bremen, the Erster Bürgermeister (First Mayor) in Hamburg, and the Regierender Bürgermeister (Governing Mayor) in Berlin. The parliament for Berlin is called the Abgeordnetenhaus (House of Representatives), while Bremen and Hamburg both have a Bürgerschaft. The parliaments in the remaining 13 states are referred to as Landtag (State Parliament).

Answer: What are the governments in Berlin, Bremen and Hamburg called?


Question: Federally, Boston is split between two congressional districts. The northern three-fourths of the city is in the 7th district, represented by Mike Capuano since 1998. The southern fourth is in the 8th district, represented by Stephen Lynch. Both are Democrats; a Republican has not represented a significant portion of Boston in over a century. The state's senior member of the United States Senate is Democrat Elizabeth Warren, first elected in 2012. The state's junior member of the United States Senate is Democrat Ed Markey, who was elected in 2013 to succeed John Kerry after Kerry's appointment and confirmation as the United States Secretary of State.

Answer: Boston is split between how many congressional districts?


Question: In the former Soviet Union, electric traction eventually became somewhat more energy-efficient than diesel. Partly due to inefficient generation of electricity in the USSR (only 20.8% thermal efficiency in 1950 vs. 36.2% in 1975), in 1950 diesel traction was about twice as energy efficient as electric traction (in terms of net tonne-km of freight per kg of fuel). But as efficiency of electricity generation (and thus of electric traction) improved, by about 1965 electric railways became more efficient than diesel. After the mid 1970s electrics used about 25% less fuel per ton-km. However diesels were mainly used on single track lines with a fair amount of traffic  so that the lower fuel consumption of electrics may be in part due to better operating conditions on electrified lines (such as double tracking) rather than inherent energy efficiency. Nevertheless, the cost of diesel fuel was about 1.5 times more (per unit of heat energy content) than that of the fuel used in electric power plants (that generated electricity), thus making electric railways even more energy-cost effective.

Answer:
What type of trains became more energy-efficient in the former Soviet Union?