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.

Ex Input:
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.

Ex Output:
When is the double indirect method of mosaic useful?

Ex Input:
The second Diadochi war began following the death of Antipater in 319 BC. Passing over his own son, Cassander, Antipater had declared Polyperchon his successor as Regent. Cassander rose in revolt against Polyperchon (who was joined by Eumenes) and was supported by Antigonus, Lysimachus and Ptolemy. In 317, Cassander invaded Macedonia, attaining control of Macedon, sentencing Olympias to death and capturing the boy king Alexander IV, and his mother. In Asia, Eumenes was betrayed by his own men after years of campaign and was given up to Antigonus who had him executed.

Ex Output:
When did Antipater die?

Ex Input:
During this time, the discovery of oil in the North Sea and the following "It's Scotland's oil" campaign of the Scottish National Party (SNP) resulted in rising support for Scottish independence, as well as the SNP. The party argued that the revenues from the oil were not benefitting Scotland as much as they should. The combined effect of these events led to Prime Minister Wilson committing his government to some form of devolved legislature in 1974. However, it was not until 1978 that final legislative proposals for a Scottish Assembly were passed by the United Kingdom Parliament.

Ex Output:
Which sea was oil discovered in?