Q: List all subsets of {1, 2, 3}. Is {1,2} ⊆ {1,2,3}? Is {1,2,3} ⊂ {1,2,3}? Subsets: ∅, {1}, {2}, {3}, {1,2}, {1,3}, {2,3}, {1,2,3} - eight = 2^3. {1,2} ⊆ {1,2,3}: yes. {1,2,3} ⊂ {1,2,3}: no (not proper - they're equal).