This task involves creating answers to complex questions, from a given passage. Answering these questions, typically involve understanding multiple sentences. Make sure that your answer has the same type as the "answer type" mentioned in input. The provided "answer type" can be of any of the following types: "span", "date", "number". A "span" answer is a continuous phrase taken directly from the passage or question. You can directly copy-paste the text from the passage or the question for span type answers. If you find multiple spans, please add them all as a comma separated list. Please restrict each span to five words. A "number" type answer can include a digit specifying an actual value. For "date" type answers, use DD MM YYYY format e.g. 11 Jan 1992. If full date is not available in the passage you can write partial date such as 1992 or Jan 1992. If you find multiple spans, please add them all as a comma separated list. Please restrict each span to five words.
Example: Passage: The outbreak of the Seven Years' War in Europe in 1756 resulted in renewed conflict between French and British forces in India. The Third Carnatic War spread beyond southern India and into Bengal where British forces captured the French settlement of Chandernagore in 1757. However, the war was decided in the south, where the British successfully defended Madras, and Sir Eyre Coote decisively defeated the French, commanded by Comte de Lally at the Battle of Wandiwash in 1760. After Wandiwash, the French capital of Pondicherry fell to the British in 1761. The war concluded with the signing of the Treaty of Paris in 1763, which returned Chandernagore and Pondichery to France, and allowed the French to have "factories" in India but forbade French traders from administering them. The French agreed to support British client governments, thus ending French ambitions of an Indian empire and making the British the dominant foreign power in India.
Question: Which french settlement did the British capture first, Chandernagore or Pondicherry
Answer type: Span
Example solution: Chandernagore
Example explanation: British captured Chandernagore in 1757 ("The Third Carnatic War spread beyond southern India and into Bengal where British forces captured the French settlement of Chandernagore in 1757") and Pondicherry in 1761 ("After Wandiwash, the French capital of Pondicherry fell to the British in 1761."). Since 1757<1761, the answer is "Chandernagore".

Problem: Passage: On 13 June 1990, the East German military officially began dismantling the Wall, beginning in Bernauer Strae and around the Mitte district. From there, demolition continued through Prenzlauer Berg/Gesundbrunnen, Helligensee and throughout the city of Berlin until that December 1990. According to estimates by the border troops, a total of around 1.7 million tonnes of building rubble was produced by the demolition. Unofficially, the demolition of the Bornholmer Strae began because of construction work on the railway. This involved a total of 300 GDR border guards and - after 3 October 1990 - 600 Pioneers of the Bundeswehr. These were equipped with 175 trucks, 65 cranes, 55 excavators and 13 bulldozers. Virtually every road that was severed by the Berlin Wall, every road that once linked from West Berlin to East Berlin, was reconstructed and reopened by 1 August 1990. In Berlin alone, 184 km of wall, 154 km border fence, 144 km signal systems and 87 km barrier ditches were removed. What remained were six sections that were to be preserved as a memorial. Various military units dismantled the Berlin/Brandenberg border wall, completing the job in November 1991. Painted wall segments with artistically valuable motifs were put up for auction in 1990 in Berlin and Monte Carlo.
Question: How many different components (including ditches and signal systems) were removed in Berlin alone?
Answer type: Number
Solution: 4.