17. Number lock and possible ways to open

Mr. Narayan is a owner of a jewelry shop, he fixed a 8 digit number code lock in is shop. If someone wants to crack the code to open safety locker, how many unique codes are possible? And what are the possible ways to open it if the repetition of number is not allowed?

 

[Note: The code has a digits from \(0\) to \(9\)].

 

 

i) There are  unique codes are possible to open the locker.

 

ii) If the repetition of number is not allowed, there are  possible ways to open.