Question: In 1950 what is the average rank?
SQL: SELECT AVG("Rank") FROM "2-15189770-1" WHERE "Year" = 1950.0;

Question: What is the building's name that is 617 / 188 in height and ranked less than 6?
SQL: SELECT "Name" FROM "2-15189770-1" WHERE "Rank" < 6.0 AND "Height feet / m" = '617 / 188';