Yang nomor 1 tolong susah banget

1)Himpunan bagian={{∅},{a},{b},{c},{a,b},{a,c},{b,c},{a,b,c}}=>Total ada 8
2)Himpunan bagian={{∅},{2},{3},{5},{7},{2,3},{2,5},{2,7},{3,5},{3,7},{5,7},{2,3,5},{2,3,7},{2,5,7},{3,5,7},{2,3,5,7}}=>Total ada 16
3)a)={{∅}}
b){{1,3,5},{1,3,7},{1,3,9},{1,5,7},{1,5,9},{1,7,9},{3,5,7},{3,5,9},{5,7,9}}
c){{1,3,5,7},{1,3,5,9},{1,5,7,9},{3,5,7,9}}