This task involves creating questions from a given passage that involve some kind of complex reasoning (including numerical reasoning). 
The generated questions must require looking at more than one part of the passage to answer. Try to use a variety of reasoning types in your questions (some of the sample reasoning types are illustrated in the 'positive examples' field) and also have a variety of answer types (spans, numbers, dates). A span is a continuous phrase taken directly from the passage or question. In such questions, the answer spans are recommended to be five words. Questions with answer type "number", are expected to start with "How many". For instance, "How long did an event last?" can be phrased as "How many years did an event last?". To increase diversity, try to create more questions for which the answer will be multiple spans. Please create questions that require AT LEAST 2 arithmetic operations as illustrated in the 'positive examples' field. You are encouraged to try DIFFERENT COMBINATIONS of operations and not just limit to the combinations shown in those examples. The more challenging questions you create, the better it is.
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Question: Passage: The United States Navy (USN) hoped to use the V-1710 in its rigid airships USS Akron (ZRS-4) and USS Macon (ZRS-5), but both were equipped with German-built Maybach VL-2 engines as the V-1710 was still in testing when the Macon was lost in February 1935 (the Akron having been lost in April 1933). The USAAC purchased its first V-1710 in December 1932. The Great Depression slowed development, and it was not until December 14, 1936 that the engine next flew in the Consolidated XA-11A testbed. The V-1710-C6 successfully completed the USAAC 150 hour Type certificate on April 23, 1937 at , the first engine of any type to do so. The engine was then offered to aircraft manufacturers where it powered the prototype Curtiss XP-37s. All entrants in the new pursuit competition were designed around it, powering the Lockheed P-38, Bell P-39 and Curtiss P-40. When war British Purchasing Commission asked North American Aviation to build the P-40 under license, NAA instead proposed their own improved aircraft design, using the V-1710 in their North American P-51 Mustang.

Answer: How many airships did the United States Navy (USN) hope to use the V-1710 in?


Question: Passage: On December 1 the 3rd Army Group guerrillas cut the Lung-hai Railway near Luowang, Neihuanggi, and east and west of Lankao. They also cut the highways at Tung-hsu , Huaiyang and Luyi. Meanwhile, the 81st Division's main force attacked Kaifeng while some of its elements attacked Lanfeng. Lowang Railway station was taken on December 15 and the Division entered Kaifeng the next day, clearing the Japanese troops and burning warehouses and a Japanese headquarters there. Meanwhile, to the southeast 2nd Cavalry Corps moved east of Boxian, encircled and attacked Shangqiu from the east and overran an airfield and burned aviation fuel there. Another force intercepted and defeated relief forces moving west from Dangshan on the Lung-hai Railway. North of the Yellow River the 36th Army Group attacked. Its new 5th Corps on December 6 attacked elements of the Japanese 1st Independent Mixed Brigade north and south of Anyang and succeeded in destroying bridges along the roads at Chi, Chun, Tang-yin and Pao-lien Temple Station. On December 13 the 47th Corps cleared Taihang Mountain and cut the Tao-tsin Railroad, taking the rail stations at Po-shan and Chang-kou. The 9th Corps attacked elements of the Japanese 35th Division between Bo'ai and Jixian, cutting communications between them and attacking the defenders on the outskirts of Jixian and a strongpoint at Mucheng. Parts of the 47th Division and demolition teams broke into Jixian for half the day, attempting to clear it of enemy troops.

Answer: How many bridges Anyang succeeded in destroying along the roads?


Question: Passage: News of the two battles reached England in August. After several months of negotiations, the government of the Duke of Newcastle decided to send an army expedition the following year to dislodge the French. They chose Major General Edward Braddock to lead the expedition. Word of the British military plans leaked to France well before Braddock's departure for North America. In response, King Louis XV dispatched six regiments to New France under the command of Baron Dieskau in 1755. The British sent out their fleet in February 1755, intending to blockade French ports, but the French fleet had already sailed. Admiral Edward Hawke detached a fast squadron to North America in an attempt to intercept them. In a second British action, Admiral Edward Boscawen fired on the French ship Alcide on June 8, 1755, capturing her and two troop ships. The British harassed French shipping throughout 1755, seizing ships and capturing seamen. These actions contributed to the eventual formal declarations of war in spring 1756.

Answer:
Between British blockading of French ports in 1755 and formal declarations of war in the following spring, how many years separated these events?