<Li> Builder: Soviet Union / Russia </Li> <Li> Displacement: 33,800 tons </Li> <Li> Operator: Russian Navy: 1 in active service of 6 built, 2 in reserve . </Li> <Li> Vanguard - class ballistic missile submarine <Ul> <Li> Builder United Kingdom </Li> <Li> Displacement: 15,680 tons </Li> <Li> Operator: Royal Navy: 4 in service </Li> </Ul> </Li>

How many submarines does russia have in service
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