user: Question: What RIAA Sales Certification was awarded to the song that had a Billboard 200 Peak of 21?
Columns: ['Year', 'Title', 'Label', 'RIAA Sales Certification', 'Billboard 200 Peak']
Types: ['real', 'text', 'text', 'text', 'real']
Sample row: [1969.0, 'Bread', 'Elektra', 'n/a', 127.0]
SQL:

assistant: SELECT "RIAA Sales Certification" FROM "Table" WHERE "Billboard 200 Peak" = 21.0;