71175
A unique feature of the telescope is its approach to image derotation : the entire telescope and optics lab , 250 tons total , rotates suspended from a mercury float bearing at the top of the tower .
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Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities:  
Answer:
 None