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.
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Question: In an effort to demonstrate peaceful intentions toward Germany, on 13 April 1941, the Soviets signed a neutrality pact with Axis power Japan. While Stalin had little faith in Japan's commitment to neutrality, he felt that the pact was important for its political symbolism, to reinforce a public affection for Germany. Stalin felt that there was a growing split in German circles about whether Germany should initiate a war with the Soviet Union. Stalin did not know that Hitler had been secretly discussing an invasion of the Soviet Union since summer 1940, and that Hitler had ordered his military in late 1940 to prepare for war in the east regardless of the parties' talks of a potential Soviet entry as a fourth Axis Power.

Answer: Who was planning an invasion of the Soviet Union?


Question: Mithridates the Great was the ruler of Pontus, a large kingdom in Asia Minor (modern Turkey), from 120 to 63 BC. Mithridates antagonised Rome by seeking to expand his kingdom, and Rome for her part seemed equally eager for war and the spoils and prestige that it might bring. In 88 BC, Mithridates ordered the killing of a majority of the 80,000 Romans living in his kingdom. The massacre was the official reason given for the commencement of hostilities in the First Mithridatic War. The Roman general Lucius Cornelius Sulla forced Mithridates out of Greece proper, but then had to return to Italy to answer the internal threat posed by his rival, Gaius Marius. A peace was made between Rome and Pontus, but this proved only a temporary lull.

Answer: Who was the leader of Pontus in the year 85 BC?


Question: Campus Martius, a reconfiguration of downtown's main intersection as a new park was opened in 2004. The park has been cited as one of the best public spaces in the United States. The city's riverfront has been the focus of redevelopment, following successful examples of other older industrial cities. In 2001, the first portion of the International Riverfront was completed as a part of the city's 300th anniversary celebration, with miles of parks and associated landscaping completed in succeeding years. In 2011, the Port Authority Passenger Terminal opened with the river walk connecting Hart Plaza to the Renaissance Center.

Answer:
In which year was Campus Martius open?