Problem: While historically, symbiosis has received less attention than other interactions such as predation or competition, it is increasingly recognized as an important selective force behind evolution, with many species having a long history of interdependent co-evolution. In fact, the evolution of all eukaryotes (plants, animals, fungi, and protists) is believed under the endosymbiotic theory to have resulted from a symbiosis between various sorts of bacteria. This theory is supported by certain organelles dividing independently of the cell, and the observation that some organelles seem to have their own nucleic acid.
What eukaryotes create various sorts of bacteria?
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Answer: unanswerable

Problem: Like other South Slavic languages, Serbo-Croatian has a simple phonology, with the common five-vowel system and twenty-five consonants. Its grammar evolved from Common Slavic, with complex inflection, preserving seven grammatical cases in nouns, pronouns, and adjectives. Verbs exhibit imperfective or perfective aspect, with a moderately complex tense system. Serbo-Croatian is a pro-drop language with flexible word order, subjectverbobject being the default. It can be written in Serbian Cyrillic or Gaj's Latin alphabet, whose thirty letters mutually map one-to-one, and the orthography is highly phonemic in all standards.
How many consonants are in Gaj's Latin alphabet?
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Answer: unanswerable

Problem: Since the 1980s, as the complexity of buildings began to increase (in terms of structural systems, services, energy and technologies), the field of architecture became multi-disciplinary with specializations for each project type, technological expertise or project delivery methods. In addition, there has been an increased separation of the 'design' architect [Notes 1] from the 'project' architect who ensures that the project meets the required standards and deals with matters of liability.[Notes 2] The preparatory processes for the design of any large building have become increasingly complicated, and require preliminary studies of such matters as durability, sustainability, quality, money, and compliance with local laws. A large structure can no longer be the design of one person but must be the work of many. Modernism and Postmodernism have been criticised by some members of the architectural profession who feel that successful architecture is not a personal, philosophical, or aesthetic pursuit by individualists; rather it has to consider everyday needs of people and use technology to create liveable environments, with the design process being informed by studies of behavioral, environmental, and social sciences.
What happened before the 1980s?
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Answer:
unanswerable