Question: What is the total number of Modern Grannies performed?
SQL: SELECT COUNT("Act") FROM "1-28180840-15" WHERE "Name/Name of Act" = 'Modern Grannies';

Question: What is the name of the performance Zhu Xiaoming performed?
SQL: SELECT "Act" FROM "1-28180840-15" WHERE "Name/Name of Act" = 'Zhu Xiaoming';

Question: How many performers are 29 that made it to the semi finals?
SQL: SELECT "Semifinal (Week)" FROM "1-28180840-15" WHERE "Age(s)" = '29';

Question: What is the name of the Zhou Jinsong's hometown?
SQL: SELECT "Hometown" FROM "1-28180840-15" WHERE "Name/Name of Act" = 'Zhou Jinsong';