209819
After improvements were made , the revised system was tested in 1940 , providing range , altitude , and azimuth for a target aircraft at up to 25 km distance .
 None
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