How many performers are 29 that made it to the semi finals?
CREATE TABLE table_28180840_15 (semifinal__week_ VARCHAR, age_s_ VARCHAR)
SELECT semifinal__week_ FROM table_28180840_15 WHERE age_s_ = "29"
### Context: CREATE TABLE table_28180840_15 (semifinal__week_ VARCHAR, age_s_ VARCHAR) ### Question: How many performers are 29 that made it to the semi finals? ### Answer: SELECT semifinal__week_ FROM table_28180840_15 WHERE age_s_ = "29"