Answer:
7! or 5040
Explanation:
The first song can be one of 7. The second song can be one of 6, because there is already one song as number one. This continues for each spot, so there are 7 × 6 × 5 × 4 × 3 × 2 × 1 combinations. This can be expressed as 7 factorial, or 7!. 7! = 5040