Question 912066: Explain why 3 to the power 7 is a multiple of 3, 3 to the power 2., 3 to the power 5, 3 to the power 6? Answer by Fombitz(32388) (Show Source):
You can put this solution on YOUR website! So it's a multiple because it has 3 as one of its factors.
The same answer applies for the other questions.