11815
We must have had something on the ball . . that was the biggest contribution that I rendered . . Johnson taught history economics and mathematics for 16 years at  Louisville  's  Central High School  before engaging the University of Kentucky in a legal test case intended to permit him to pursue further graduate study there .
 city of headquarters: Louisville, Central High School
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:  Louisville, Central High School 
Answer:
 city of headquarters: Louisville, Central High School