\(2Fe+3Cl_2\rightarrow2FeCl_3\)

\(FeCl_2+2AgNo_3\rightarrow Fe\left(NO_3\right)_2+2AgCl\)

\(CuSO_4+2NaOH\rightarrow Cu\left(OH\right)_2+Na_2SO_4\)

\(K_2O+H_2O\rightarrow2KOH\)

\(2Al\left(OH\right)_3+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+6H_2O\)

\(Zn+2HCl\rightarrow ZnCl_2+H_2\)

\(4FeS_2+11O_2\rightarrow2Fe_2O_3+8SO_2\)

a) \(A=\sqrt{2.8}+\sqrt{9}.\sqrt[3]{27}=\sqrt{16}+3-3=4\)

b) \(B=\dfrac{1\left(2+\sqrt{3}\right)}{4-3}+\dfrac{2\left(\sqrt{5}-\sqrt{3}\right)}{5-3}\)

\(=2+\sqrt{3}+\sqrt{5}-\sqrt{3}=2+\sqrt{5}\)

10 D

Đọc là /i:/, còn lại là /e/

11 A

Đọc là /ɒ', còn lại là /əʊ/

1 have been studying

2 is ringing

3 Have - finished

4 is called

5 were - doing

6 Unmarried

7 unbelievable

8 attentively

À đúng rồi, câu đấy nó ở trên đầu nên không để ý

19 are=>be

20 using=>to use

21 bench=>benches

22 20=>20^th

23 three times=>twice

24 Art=>Music

25 many=>often

26 slow=>slowly

27 roar=>roared

28 wash=>washes

29 and=>but

30 built=>build

1 Lan goes to the supermarket on foot

2 Our garden has many flowers

3 He has balck hair

4 We mustn't finish the task today

5 Are there 23 students in your class?

6 Lan is not as young as Minh

1 c

2 a

3 c

4 c

5 b

6 d

7 a

8 d

9 b

10 c

1 village

2 mountain

3 towel

4 avenue

5 city

6 town

7 island

8 stream

1 cunning  

2 generous

3 brave

4 cheerful

5 greedy

6 cruel

7 wicked

8 evil

9 fierce

10 mean