user: Question: What was the free dance score in the event where compulsory dance score was 15.99? 
Columns: ['Event', 'Season', 'Compulsory Dance (CD)', 'Original Dance (OD)', 'Free Dance (FD)', 'Combined Total Score']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['European Figure Skating Championships', '2008 - 2009', '23.75', '44.56', '66.67', '134.98']
SQL:

assistant: SELECT "Free Dance (FD)" FROM "Table" WHERE "Compulsory Dance (CD)" = '15.99';