a. 

\(198+232-98-32\\ =\left(198-98\right)+\left(232-32\right)\\ =100+200\\ =300\)

b.

\(567+538-326+62\\ =\left(567-326\right)+\left(538+62\right)\\ =241+600\\ =841\)

c.

\(567-32-68\\ =535-68\\ =467\)

d.

\(2391-147-25.3\\ =2391-147-75\\ =2169\)

e.

\(91.25-91.13-91.12\\ =91.\left(25-13-12\right)\\ =0\)

f.

\(17-8+47.12-27.9-27.11\\ =\left(9+564\right)-27.\left(9-11\right)\\ =573--54\\ =627\)

g.

\(24.42-35.24-24.7\\ =24.\left(42-35-7\right)\\ =0\)

h.

\(42.13-22.5+42.7-15.22\\ =\left(42.13+42.7\right)+\left(-22.5-15.22\right)\\ =42.\left(13+7\right)+22.\left(-5-15\right)\\ =840-440\\ =400\)

k.

\(125:4-25:4\\ =\left(125-25\right):4\\ =100:4\\ =25\)

m.

\(1159:125-159:125\\ =\left(1159-159\right):125\\ =8\)

1, B

2, D

3, B

4, A

5, D

II,

1, C

2, D

3, D

4, B

5, B

em nghĩ 3 C mới đúng chứ ạ

Cấu trúc : prefer Ving to Ving mà chị???

I,

1, C

2, A

3, C. sending (mới đúng nhé, không có ''to")

4, B

5, A

II, 

1, It exists in the Central Highlands of Viet Nam.

2, The Gong Festival is held annually in the Central Highlands.

3, Artists  give gong performances, highlighting the gong culture of their own province.

4, No, they aren't

5, No, it isn't

C

1, Your house is bigger than my house.

2, Jenny dislikes reading poetry.

II, 

Không gạch chân sao làm ạ?