CREATE TABLE table_name_30 (sub_parish__sokn_ VARCHAR(255), year_built VARCHAR(255), location_of_the_church VARCHAR(255))
What is the Sub-Parish (Sokn) that was built in 1957 in the location of Stavang?
    
SQL: SELECT sub_parish__sokn_ FROM table_name_30 WHERE year_built = "1957" AND location_of_the_church = "stavang"