question: What is the GDP (billion US$) of the country that has a GDP per capita (US$) of 8,861?
answer: SELECT gdp__billion_us$_ FROM table_name_29 WHERE gdp_per_capita__us$_ = "8,861"
context: CREATE TABLE table_name_29 (gdp__billion_us$_ VARCHAR, gdp_per_capita__us$_ VARCHAR)