1)
Why does the Torah repeat the fact that Aharon died on Hor ha'Har?
1.
Oznayim la'Torah: To stress the fact that that is where he actually died, and when the Torah writes in Eikev Devarim, 10:6 that he died in Moseirah, it means that he was eulogized there, as Rashi explains there in Pesukim 6 & 7.