What happenes to downloaded music of songs deleted from a followed playlist

[LDMartin1959]

Two question:

First, if I've downloaded files from a playlist I'm following and the creator of that playlist deletes songs from that list, what happens to the downloaded tracks on my device?

Second, is there a way to delete individual tracks I've downloaded from a playlist I'm following? There doesn't seem to be an option to delete tracks individually, just the entire list of downloaded files.