Question: The largest ship in the "Imperator" class ocean liners had how many gross register tons?
Related documents: [0]  [DOC] The "Imperator" class ocean liners were a series of three ocean liners designed for the Hamburg America Line, commonly known as "HAPAG". These three ships were commissioned by the chairman of HAPAG Albert Ballin. Namely the "Imperator" (1912), the "Vaterland" (1913) and the largest, the "Bismarck" (1914). These liners were over 50,000 tons, sported three funnels and had a length ranging from 906 ft (276 m) to 955.8 ft (291.3 m). To this day, the "Vaterland" is the largest passenger ship operated by a German shipping company. [END] 
[1]  [DOC] RMS "Majestic was a White Star ocean liner working on the North Atlantic run, originally launched in 1914 as the Hamburg America Line liner SS "Bismarck. At 56,551 gross register tons, she was the largest ship in the world until completion of  in 1935. [END] 
Answer: 
56,551
56,551