Question: how many possible song combinations?
Answer: To find out how many notes there are in a 3-minute song we need to set the tempo. A typical tempo is 120 bpm in 4/4-time which means that there are 240 eights notes per minute, so 720 in total for a 3-minute song. So, the total number of songs possible is 7^720 which is approximately 3 followed by 608 zereos.