CÂU 2. (1,5 I M)N I DUNG I M 33 2A BC B D2 3 4P A B C A B A B C D A...

2 .

2 2

a b a b c a b a b c

3 2

a b c

bc b c

3 3 . .

3 3

2 3

a b a b c d a b a b c a b c d

b c

a b a b c a b c d

b d b d

4 4.

4 3 4

a b a b c d

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b d