instruction:
This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.
question:
Passage: 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:
In the US, electric traction became more energy-efficient than what?


question:
Passage: Between 1925 and 1940, philanthropic foundations, especially ones connected with the Rockefellers, contributed about $7 million to support the Yale Institute of Human Relations and the affiliated Yerkes Laboratories of Primate Biology. The money went toward behavioral science research, which was supported by foundation officers who aimed to "improve mankind" under an informal, loosely defined human engineering effort. The behavioral scientists at Yale, led by President James R. Angell and psychobiologist Robert M. Yerkes, tapped into foundation largesse by crafting research programs aimed to investigate, then suggest, ways to control, sexual and social behavior. For example, Yerkes analyzed chimpanzee sexual behavior in hopes of illuminating the evolutionary underpinnings of human development and providing information that could ameliorate dysfunction. Ultimately, the behavioral-science results disappointed foundation officers, who shifted their human-engineering funds toward biological sciences.
answer:
How much did philanthropic foundations donate between 1935 and 1940?


question:
Passage: In philosophy, emotions are studied in sub-fields such as ethics, the philosophy of art (for example, sensory–emotional values, and matters of taste and sentimentality), and the philosophy of music (see also Music and emotion). In history, scholars examine documents and other sources to interpret and analyze past activities; speculation on the emotional state of the authors of historical documents is one of the tools of interpretation. In literature and film-making, the expression of emotion is the cornerstone of genres such as drama, melodrama, and romance. In communication studies, scholars study the role that emotion plays in the dissemination of ideas and messages. Emotion is also studied in non-human animals in ethology, a branch of zoology which focuses on the scientific study of animal behavior. Ethology is a combination of laboratory and field science, with strong ties to ecology and evolution. Ethologists often study one type of behavior (for example, aggression) in a number of unrelated animals.
answer:

Along with the philosophies of music and art, what field of philosophy doesn't study emotions?