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In Cambodia , an intricate ecology and age-old economy depend on the ebb and flow of the great lake fed by the Mekong , Tonle Sap , which can swell fourfold during the rainy season .
 location contains: Cambodia, Mekong
Given options, please tell me the relationships of all the listed entity pairs.Output format is "relation1: word1, word2; relation2: word3, word4". 
Option: ethnicity, place lived, geographic distribution, company industry, country of administrative divisions, administrative division of country, location contains, person of company, profession, ethnicity of people, company shareholder among major shareholders, sports team of location, religion, neighborhood of, company major shareholders, place of death, nationality, children, company founders, company founded place, country of capital, company advisors, sports team location of teams, place of birth 
Text: {0} 
 Entity Pairs:  Cambodia, Mekong 
Answer:
 location contains: Cambodia, Mekong