Jerry asked the doctors to remove the bullets from his body because he was allergic to them.
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设A∩B=A,则
A∪B=A
B. A∪B=B
C. B-A=Φ
D. B⊂A
设A∩B=A,则下列选项中正确的是
A∪B=A
B. A∪B=B
C. B-A=Φ
D. B⊂A
设A∪B=B,则下列选项中错误的是
A⊆B
B. A∩B=A
C. A-B=Φ
D. B-A=Φ
设A和B是集合, Φ是空集,则A-B=A当且仅当B=Φ。
A. 对
B. 错