Question

(b) how do people get transformed from humming tunes to become professional musicians​

Answer 1

in humming tunes, Whenever someone heard solos ,especially phrase solos that goes along with some phrase of the song to become professional musicians.

Answer 2

Answer:

Singing or realistically speaking, expressing one's emotion musically,sometimes takes a serious turn. This desire to showcase musical expression in public domain then trasforms into serious business prefession,and from here the musical journey begins.