CREATE TABLE table_2668 ("Event" TEXT, "Season" TEXT, "Compulsory Dance  ( CD ) " TEXT, "Original Dance  ( OD ) " TEXT, "Free Dance  ( FD ) " TEXT, "Combined Total Score" TEXT)

What was the free dance score in the event where compulsory dance score was 15.99?
SELECT "Free Dance (FD)" FROM table_2668 WHERE "Compulsory Dance (CD)" = '15.99'
SELECT "Free Dance (FD)" FROM "table_2668" WHERE "Compulsory Dance (CD)" = '15.99'