620
The Israeli Air Defense Command is the Israel Defense Forces unit responsible for the surface front of  Israel  's air defense complementing the air defense provided by  Israeli Air Force  squadrons .
 country of headquarters: Israel, Israeli Air Force
Given options, please tell me the relationships of all the listed entity pairs.Output format is "relation1: word1, word2; relation2: word3, word4". 
Option: cities of residence, top members employees, members, alternate names, origin, state or provinces of residence, title of person, spouse, city of headquarters, NA, founded by, state or province of headquarters, employee of, countries of residence, country of birth, founded, subsidiaries, country of headquarters 
Text: {0} 
 Entity Pairs:  Israel, Israeli Air Force 
Answer:
 country of headquarters: Israel, Israeli Air Force