Share This Article 1. The Area-51 facility was established in 1955 to develop this aircraft. The SR-71 The F-111 The F-117 The U-2 2. On 7 April 1862 this Confederate stronghold on the Mississippi surrendered. Fort Donelson Island No. 10 Cairo, Illinois Vicksburg, Mississippi 3. This country’s general staff was the first to use the “staff ride” as a training exercise. Great Britain Germany Austria France Loading …