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When the US Congress approved one hundred million dollars in aid to Serbia last month , it stipulated the aid would stop flowing if Belgrade has n't cooperated with the tribunal by March 31st .
 organization: the US Congress; money: one hundred million dollars; geographical social political: Serbia; date: last month; geographical social political: Belgrade; date: March 31st
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: date, organization, person, geographical social political, national religious political, facility, cardinal, location, work of art, law, event, product, ordinal, percent, time, quantity, money, language 
Text: {0} 
Answer:
 organization: the US Congress; money: one hundred million dollars; geographical social political: Serbia; date: last month; geographical social political: Belgrade; date: March 31st