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.
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Question: The double indirect method can be used when it is important to see the work during the creation process as it will appear when completed. The tesserae are placed face-up on a medium (often adhesive-backed paper, sticky plastic or soft lime or putty) as it will appear when installed. When the mosaic is complete, a similar medium is placed atop it. The piece is then turned over, the original underlying material is carefully removed, and the piece is installed as in the indirect method described above. In comparison to the indirect method, this is a complex system to use and requires great skill on the part of the operator, to avoid damaging the work. Its greatest advantage lies in the possibility of the operator directly controlling the final result of the work, which is important e.g. when the human figure is involved. This method was created in 1989 by Maurizio Placuzzi and registered for industrial use (patent n. 0000222556) under the name of his company, Sicis International Srl, now Sicis The Art Mosaic Factory Srl.

Answer: When is the double indirect method of mosaic useful?


Question: When the GHMC was created in 2007, the area occupied by the municipality increased from 175 km2 (68 sq mi) to 650 km2 (250 sq mi). Consequently, the population increased by 87%, from 3,637,483 in the 2001 census to 6,809,970 in the 2011 census, 24% of which are migrants from elsewhere in India,:2 making Hyderabad the nation's fourth most populous city. As of 2011[update], the population density is 18,480/km2 (47,900/sq mi). At the same 2011 census, the Hyderabad Urban Agglomeration had a population of 7,749,334, making it the sixth most populous urban agglomeration in the country. The population of the Hyderabad urban agglomeration has since been estimated by electoral officials to be 9.1 million as of early 2013 but is expected to exceed 10 million by the end of the year. There are 3,500,802 male and 3,309,168 female citizens—a sex ratio of 945 females per 1000 males, higher than the national average of 926 per 1000. Among children aged 0–6 years, 373,794 are boys and 352,022 are girls—a ratio of 942 per 1000. Literacy stands at 82.96% (male 85.96%; female 79.79%), higher than the national average of 74.04%. The socio-economic strata consist of 20% upper class, 50% middle class and 30% working class.

Answer: What was the area of Hyderabad before the GHMC?


Question: Measuring corruption statistically is difficult if not impossible due to the illicit nature of the transaction and imprecise definitions of corruption. While "corruption" indices first appeared in 1995 with the Corruption Perceptions Index CPI, all of these metrics address different proxies for corruption, such as public perceptions of the extent of the problem.

Answer:
Why is it difficult to measure corruption?