7191
Production of the QF 3.7 - inch ( 94 " mm ) began in 1937 ; this gun was used on mobile carriages with the field army and transportable guns on fixed mountings for static positions .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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