Problem: Since the middle of the 19th century, Masonic historians have sought the origins of the movement in a series of similar documents known as the Old Charges, dating from the Regius Poem in about 1425 to the beginning of the 18th century. Alluding to the membership of a lodge of operative masons, they relate a mythologised history of the craft, the duties of its grades, and the manner in which oaths of fidelity are to be taken on joining. The fifteenth century also sees the first evidence of ceremonial regalia.
What kind of an oath do Masons refuse to take when they join?
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Answer: unanswerable

Problem: With the defeat of Marshal Bazaine's Army of the Rhine at Gravelotte, the French were forced to retire to Metz, where they were besieged by over 150,000 Prussian troops of the First and Second Armies. Napoleon III and MacMahon formed the new French Army of Chalons, to march on to Metz to rescue Bazaine. Napoleon III personally led the army with Marshal MacMahon in attendance. The Army of Chalons marched northeast towards the Belgian border to avoid the Prussians before striking south to link up with Bazaine. The Prussians, under the command of Field Marshal Count Helmuth von Moltke, took advantage of this maneuver to catch the French in a pincer grip. He left the Prussian First and Second Armies besieging Metz, except three corps detached to form the Army of the Meuse under the Crown Prince of Saxony. With this army and the Prussian Third Army, Moltke marched northward and caught up with the French at Beaumont on 30 August. After a sharp fight in which they lost 5,000 men and 40 cannons, the French withdrew toward Sedan. Having reformed in the town, the Army of Chalons was immediately isolated by the converging Prussian armies. Napoleon III ordered the army to break out of the encirclement immediately. With MacMahon wounded on the previous day, General Auguste Ducrot took command of the French troops in the field.
What factor forced the French to retreat to Metz?
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Answer: the defeat of Marshal Bazaine's Army

Problem: In 1958 as part of an experiment, Operation Argus, the United States Navy detonated an atomic bomb 160 kilometres (100 mi) high in the upper atmosphere about 175 kilometres (109 mi) southeast of the main island.
When did the upper atmosphere detonate an atomic bomb?
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Answer:
unanswerable