Answer:
9
Step-by-step explanation:
If I’m understanding you correctly, the answer would be nine. Any number with a 9 in the one’s place (unit digit) would still have a nine in that place after being cubed.
29³=24,389
69³=328,509
Nobody will be able to give an accurate response to this question without seeing the tally chart sorry
By definition, the number
is the ratio between the circumference and the diameter:

This implies that

And so your circumference is 
X/.5 > 6
(the > has a line under it but idk how to type that lol)