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.

From 7 September 1940, one year into the war, London was bombed by the Luftwaffe for 57 consecutive nights. More than one million London houses were destroyed or damaged and more than 40,000 civilians were killed, almost half of them in London. Ports and industrial centres outside London were also attacked. The main Atlantic sea port of Liverpool was bombed, causing nearly 4,000 deaths within the Merseyside area during the war. The North Sea port of Hull, a convenient and easily found target or secondary target for bombers unable to locate their primary targets, was subjected to 86 raids in the Hull Blitz during the war, with a conservative estimate of 1,200 civilians killed and 95 percent of its housing stock destroyed or damaged. Other ports including Bristol, Cardiff, Portsmouth, Plymouth, Southampton and Swansea were also bombed, as were the industrial cities of Birmingham, Belfast, Coventry, Glasgow, Manchester and Sheffield. Birmingham and Coventry were chosen because of the Spitfire and tank factories in Birmingham and the many munitions factories in Coventry. The city centre of Coventry was almost destroyed, as was Coventry Cathedral.
How many nights did the Luftwaffe bomb London?

The city remained in the hands of Christian troops until 1102, when the Almoravids retook the city and restored the Muslim religion. Although the self-styled 'Emperor of All Spain', Alfonso VI of León and Castile, drove them from the city, he was not strong enough to hold it. The Christians set it afire before abandoning it, and the Almoravid Masdali took possession on 5 May 1109. The event was commemorated in a poem by Ibn Khafaja in which he thanked Yusuf ibn Tashfin for the city's liberation.The declining power of the Almoravids coincided with the rise of a new dynasty in North Africa, the Almohads, who seized control of the peninsula from the year 1145, although their entry into Valencia was deterred by Ibn Mardanis, King of Valencia and Murcia until 1171, at which time the city finally fell to the North Africans. The two Muslim dynasties would rule Valencia for more than a century.
In what year did Christian troops lose control of Valencia?

One of the oldest observatories in South America is the Quito Astronomical Observatory. Founded in 1873 and located 12 minutes south of the Equator in Quito, Ecuador. The Quito Astronomical Observatory is the National Observatory of Ecuador and is located in the Historic Center of Quito and is managed by the National Polytechnic School.

What observatory is the National Observatory of Ecuador?