1 or 4 , depending on your point of view.
9, 19, 29, 39, 49, 59, 69, 79, 89, 90, 91, 92
You can get eleven 9s from 99. This is because when you take 99 and divide it by 9, the result is 11. Thus, 99 contains eleven instances of the digit 9.
5
Nine of them
79
Eleven.
24 of them with a remainder of 2
Exactly 6 of them
10 times
The GCF of 9s and 63s^3 is 9s.
20
111 of them with a remainder of 1