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A.32                                                        B.8

C.5                                                          D.3

①{a,b}={b,a}  ②{a,b}{b,a}  ③={}  ④{0}=  ⑤{0}  ⑥0∈{0},

A.6個(gè)                                                      B.5個(gè)

C.4個(gè)                                                      D.3個(gè)及3個(gè)以下

A.4                              B.3                              C.2                              D.1

①1∈{0，1，2}  ②{1}∈{0，1，2}  ③{0，1，2}{0，1，2}  ④{0，1，2}

⑤{0，1，2}＝{2，0，1}

A.1                                                             B.2    

C.3                                                             D.4

①空集沒有子集  ②空集是任何一個(gè)集合的真子集  ③任何一個(gè)集合必有兩個(gè)或兩個(gè)以上的子集  ④如果集合BA,那么若元素不屬于A，則必不屬于B

A.1                                                         B.2 

C.3                                                         D.4

A.{a}A                                            B.aA

C.{a}∈A                                             D.aA