Answer :

[tex]\{1;\ 2;\ 3\}\\\\subsets:\\\{1\};\ \{2\};\ \{3\}\\\{1;2\};\ \{1;3\};\ \{2;3\}\\\{1;2;3\}\\\{\O\}\\\\Answer:8\ subsets[/tex]
AL2006
Subsets can have zero, 1, 2, or 3 members.

Zero members . . 1 subset
1 member . . . . . 3 subsets
2 members . . . . 3 subsets
3 members . . . . 1 subset

Total . . . . . . . . . 8 subsets