What range of numbers(integers) can be represented using base 3, 3's complement representation using 4 digits

Answer 1

I won't give you the fomula- figure it out yourself.
Below are the possible combinations of 3 bit base 3; you decide on how a forth bit (used as a complement) would affect it.

000
001
002
010
011
012
020
021
022
100
101
102
110
111
112
120
121
122
200
201
202
210
211
212
220
221
222