In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
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Question: Why are areas in Neolithic sudan no longer settled?, Context: During the Neolithic Era, before the onset of desertification, around 9500 BCE the central Sudan had been a rich environment supporting a large population ranging across what is now barren desert, like the Wadi el-Qa'ab. By the 5th millennium BCE, the people who inhabited what is now called Nubia, were full participants in the "agricultural revolution", living a settled lifestyle with domesticated plants and animals. Saharan rock art of cattle and herdsmen suggests the presence of a cattle cult like those found in Sudan and other pastoral societies in Africa today. Megaliths found at Nabta Playa are overt examples of probably the world's first known archaeoastronomy devices, predating Stonehenge by some 2,000 years. This complexity, as observed at Nabta Playa, and as expressed by different levels of authority within the society there, likely formed the basis for the structure of both the Neolithic society at Nabta and the Old Kingdom of Egypt.

Answer: now barren desert

Question: where was the first stone of the city placed in the ground, Context: On 12 December 1911, during the Delhi Durbar, George V, then Emperor of India, along with Queen Mary, his Consort, made the announcement that the capital of the Raj was to be shifted from Calcutta to Delhi, while laying the foundation stone for the Viceroy's residence in the Coronation Park, Kingsway Camp. The foundation stone of New Delhi was laid by King George V and Queen Mary at the site of Delhi Durbar of 1911 at Kingsway Camp on 15 December 1911, during their imperial visit. Large parts of New Delhi were planned by Edwin Lutyens (Sir Edwin from 1918), who first visited Delhi in 1912, and Herbert Baker (Sir Herbert from 1926), both leading 20th-century British architects. The contract was given to Sobha Singh (later Sir Sobha Singh). Construction really began after World War I and was completed by 1931. The city that was later dubbed "Lutyens' Delhi" was inaugurated in ceremonies beginning on 10 February 1931 by Lord Irwin, the Viceroy. Lutyens designed the central administrative area of the city as a testament to Britain's imperial aspirations.

Answer: site of Delhi Durbar of 1911 at Kingsway Camp

Question: What are bigger squares used for?, Context: A tile mosaic is a digital image made up of individual tiles, arranged in a non-overlapping fashion, e.g. to make a static image on a shower room or bathing pool floor, by breaking the image down into square pixels formed from ceramic tiles (a typical size is 1 in 1 in (25 mm 25 mm), as for example, on the floor of the University of Toronto pool, though sometimes larger tiles such as 2 in 2 in (51 mm 51 mm) are used). These digital images are coarse in resolution and often simply express text, such as the depth of the pool in various places, but some such digital images are used to show a sunset or other beach theme.

Answer:
express text