Table: discography_tracks
Columns: track_no
track
original_artist
soloist_s
vocal_percussionist
arranger_s

Question: What is the track whent the vocal percussionist is unknown?
SQL: SELECT "track" FROM discography_tracks WHERE "vocal_percussionist" = 'unknown'

Question: Who is the arranger when the vocal percussionist is Alexei Kalveks and Dave Brennan?
SQL: SELECT "arranger_s" FROM discography_tracks WHERE "vocal_percussionist" = 'Alexei Kalveks and Dave Brennan'

Question: What is the original artist when the vocal percussionist is Alexei Kalveks?
SQL: SELECT "original_artist" FROM discography_tracks WHERE "vocal_percussionist" = 'Alexei Kalveks'