Answer:
8 possible combinations
Assuming R 1, R 2 and R 3 be three different Resistance
1- all three in series
2-all three in parallel
3- R 1 and R 2 in series and parallel with R 3
4-R 1 and R 3 in series and parallel with R 2
5-R 2 and R 3 in series and parallel with R 1
6- R 1 and R 2
in parallel and series with R 3
7-R 1 and R 3 in parallel and series with R 2
8-R 2 and R 3 in V with R 1