In the movie Casablanca the three different diegetic sounds are used as the dialogue between the characters in the bar.
Step-by-step explanation:
The filmmaker includes the three diegetic sounds that are used as the dialogue between the characters in the bar. The non-diegetic sounds are the gun shot sounds made in the beginning of the movie.
If it is a diegetic music then it gives a spatial and temporal understanding of the scene because it shows where the music is coming from.
The diegetic sounds are realistic such as fight scenes in a movie when the character and viewers intercept the different sounds. If the characters in the film can hear the music then it is a diegetic sound and if the background music not heard by the characters in the movie is known as non-diegetic.