A= \(\frac{2+\sqrt{3}}{2-\sqrt{3}}-\frac{2-\sqrt{3}}{2+\sqrt{3}}\)
B= \(\frac{3}{4-\sqrt{7}}-\frac{3}{4+\sqrt{7}}\)

1. Why don't we go for a picnic on the weekend?
=> Let's
2. Let's go to work by bus.
=> What about
3. Nga is a good English speaker.
=> Nga speaks
4. Unless you get a visa. You can't visit the United States.
=> If you
5. If you don't succeed, you'll have to try it again.
=> Unless
6. I suggest collecting unused cothes.
=> Let's
7. Ba is tired. He stayed up late watching TV.
=> Because
8. Hoa was careless, so broke the cup.
=> Since
9. We were disappointed. She didn't keep her promise. (Adj + that)
=>
10. It was raining, so we decided to postpone our camping.
=> Since
11. She wants them to sing a song.
=> She suggests they
12. She couldn't join us beacause she was busy.
=> She was busy, so
13. Shall we go to the cinema tonight?
=> What about
14. Why don't we use energy-saving bulbs?
=> I suggest
15. Although she was not beatiful, she took part in a beauty contest.
=> She wasn't beatiful but
16. Work hard and you'll pass the exam.
=> If you
17. If you don't start working hard now, you won't be able to pass the final exam.
=> Unless
18. We are delighted. You passed your English exam.
=> We are delighted
19. She was tired and therefore she wanted to go home.
=> She wanted to go home because
20. Tet is a festival. Tet occurs in late January or early February. (which)
=> Tet is a festival
21. The pupil gets the scholarship. He is very poor. (who)
=> The pupil
22. Auld Lang Syne is a song. Auld Lang Syne is sung on New Year's Eve. (which)
=> Auld Lang Syne is a song
23. Have you ever spoken to the people? They live next door. (who)
=> Have you ever spoken to the people
24. Is this the book? You want me to read it? (which)
=>
25. My friend Tom can compose songs. Tom sings Western folk songs very well. (who)
=> My friend,
26. He often tells lies but many people believe him.
=> Although
27. He is very tired but he has to finish his homework. (even though)
=> Even though
---
B. Thì hiện tại hoàn thành và thì quá khứ đơn
1. We have learnt Englist for 6 years.
=> We started
2. It's three years since I last saw Nam.
=> I haven't
3. I last wrote to my uncle in July.
=> I haven't
4. Minh has collected stamps since 2000.
=> Minh began
5. It's a long time since we became close friends.
=> We have
6. I haven't gone to Da Lat for a long time.
=> I last
7. The last time I visited my grandparents was last summer.
=> I haven't
8. My family have lived in Lien Huong for 10 years.
=> My family started
9. I last saw him two days ago.
=> I have
10. How long have you bought this car?
=> When did ?

1. \(\sqrt{3}\) - \(2\sqrt{12}\) + \(3\sqrt{27}\) - \(4\sqrt{48}\) + \(5\sqrt{75}\)
2. \(\sqrt{175}\) - \(2\sqrt{112}\) - \(3\sqrt{63}\) - \(2\sqrt{28}\) + \(\sqrt{7}\)
3. \(3\sqrt{75}\) - \(\frac{12}{\sqrt{2}}\) - \(30\sqrt{1\frac{1}{3}}\) + \(\sqrt{75}\)
4. (\(2\sqrt{3}\) -\(\sqrt{12}\) +\(2\sqrt{27}\) ) : \(3\sqrt{3}\)
5. (\(4\sqrt{2}\) - \(\sqrt{72}\) - \(3\sqrt{50}\) ) \(\sqrt{2}\) -\(4\sqrt{25}\) + \(1\)

Christmas
Two popolar traditions at Chirstmas are: decorating the home and singing the Christmas carols. The home is the center of the Christmas celebration. Inside, an evergreen tree is usually placed in the corner of the Living room. Children and their parents wrap string of colorful lights around the tree, they hang ornaments on the branches. A star or angle often crowns the top. Careful-wrapped gifts are placed beneath. Outside, families often string lights around the windows and wind light around tress and shrubs in the front yard. As the families decorate their homes, they often put on Christmas record. Almost every family has at least one favorite album or compact disc. School children of all ages perform Christmas tree to sing traditional songs Such as Jingle bells and Silent night and the give presents to each other.
1. What are the popular traditions at the chrismas?
=>
2. Where is the evergreen put?
=>
3. How do they decorate the Christmas tree?
=>
4. What do the family members often do on Christmas' Eve?
=>
5. What do they do as they decorate their home?
=>

Cho 11,2 gam Fe tác dụng vừa đủ với 175 gam dung dịch CH₃COOH.
a) Viết phương trình phản ứng xảy ra.
b) Tính thể tích khí H₂ sinh ra ở dktc.
c) Tính nồng độ phần trăm của dung dịch muối thu được sau phản ứng.

Cho mẫu kim loại Mg tác dụng vừa đủ với dung dịch axit axetic 30%. Sau phản ứng thu được 3,36 lít khí (dktc)
a) Tính khối lượng kim loại tham gia phả ứng
b) tính nồng độ phần trăm của dung dịch muối thu được sau phản ứng.
__________
Tính giúp mình với ghi lời giải vào luôn ạ

Oanh là một học sinh lớp 9A. sáng ngày mai bạn ấy phải trình bày bài diễn văn trước lớp. Em hãy giúp bạn ấy viết bài chuẩn bị.
TOPIC: REDUCING GARBAGE
*collect plastic bags.
*not keep solid waste with food waste
*put different kinds of waste in different places
*(your own idead)
_____________________
giúp mình với

Oanh là một học sinh lớp 9A. sáng ngày mai bạn ấy phải trình bày bài diễn văn trước lớp. Em hãy giúp bạn ấy viết bài chuẩn bị.
TOPIC: REDUCING GARBAGE
*collect plastic bags.
*not keep solid waste with food waste
*put different kinds of waste in different places
*(your own idead)
_____________________
giúp mình với