Premise: Convoy PQ-4 was the fifth of the Arctic Convoys of World War II by which the Western Allies supplied material aid to the Soviet Union in its fight with Nazi Germany. The Convoy sailed from Hvalfjord, Iceland on 17 November 1941 and arrived at Archangelsk on 28 November 1941.
Hypothesis: There were four Arctic Convoys in WWII before Convoy PQ-4