Which friend of Krzysztof Kieślowski wrote the musical score to the film known in French as "Trois colours"?
Three Colours trilogy: The "Three Colours" trilogy (Polish: "Trzy kolory" , French: "Trois couleurs" ) is a three-part film series directed by Krzysztof Kieślowski. Three Colours trilogy:  All three were co-written by Kieślowski and Krzysztof Piesiewicz (with story consultants Agnieszka Holland and Sławomir Idziak) and have musical scores by Zbigniew Preisner.
i don't know