Câu 2

\((1) MnO_2 + 4HCl \to MnCl_2 + Cl_2 + 2H_2O\\ (2) Cl_2 + H_2 \xrightarrow{as} 2HCl\\ (3) 3Cl_2 + 2Fe \xrightarrow{t^o} 2FeCl_3\\ (4) 2FeCl_3 + Fe \to 3FeCl_2\\ (5) 2NaOH + Cl_2 \to NaCl + NaClO + H_2O\)

\((1) 4Al + 3O_2 \xrightarrow{t^o} 2Al_2O_3\\ (2) 2Fe + 3Cl_2 \xrightarrow{t^o} 2FeCl_3\\ (3) C + O_2 \xrightarrow{t^o} CO_2\\ (4) 2KMnO_4 \xrightarrow{t^o} K_2MnO_4 + MnO_2 + O_2\\ (5) 4P + 5O_2 \xrightarrow{t^o} 2P_2O_5\\ (6) 2KClO_3 \xrightarrow{t^o} 2KCl + 3O_2\\ (7) Fe + H_2SO_4 \to FeSO_4 + H_2\\ (8) Cu + 2H_2SO_4 \to CuSO_4 + SO_2 + 2H_2O\\ (9) 2Fe + 6H_2SO_4 \to Fe_2(SO_4)_3 + 3SO_2 + 6H_2O\\ (10) 2Al + 6H_2SO_4 \to Al_2(SO_4)_3 + 3SO_2 + 6H_2O\)

1. Brush your teeth after meals.

2. Don't play soccer in the street

3. Wash and iron your own clothes.

4. Don't eat too much candy.

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1. She is interested in/ fond of/ keen on playing tennis.

2. No house in the street is older than my house.

3. Although the test was difficult, many students did it well. 

4. It's very important to keep the environment clean.

5. What a wonderful holiday they have!

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1. My sister is a fast runner.

2. Hoang plays football badly.

3. Linh is good at swimming.

4. Peter's favourite sport is badminton.

5. Jack is fatter than Mike.

6. Hugo is interested in playing sports in his free time.

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1. There isn't a bookshelf in my room.

2. Ha is harder than Quang.

3. What a lovely baby!

4. Viết lại bằng từ gì nhỉ?

Question 2: David has volunteered for 2 years

Question 3: I think collecting stamps is interesting

mình làm câu 2, 3 rồi nhé

https://hoc24.vn/cau-hoi/anh-chi-giup-em-tieng-anh-7-cau-1-va-2-voi-a-chieu-e-thi-aem-cam-on-anh-chi-rat-nhieu-a.3054793966970

câu 1: Lan had a high fever, so she stayed home from school yesterday

a: \(\left\{{}\begin{matrix}3x+6y=4\\x+4y=2\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}y=\dfrac{1}{3}\\x=\dfrac{2}{3}\end{matrix}\right.\)