A cadence marks is that the end of the song, the beginning of an introduction, the end of the phrase or the key signature

Answer 1

A cadence marks the end of a phrase in music, providing a sense of punctuation or closure. It signifies a momentary pause or resolution before moving on to the next musical idea. While cadences can occur at various points within a song, they typically appear at the end of a phrase or a section. The key signature does not directly correspond to a cadence, but it helps determine the tonal center or key in which the music is written.