Hỗn hợp E gồm chất X (C_mH_2m+4O₄N₂, là muối của axit cacboxylic hai chức) và chất Y (C_nH_2n+3O₂N, là muối của axit cacboxylic đơn chức). Đốt cháy hoàn toàn 0,1 mol E cần vừa đủ 0,26 mol O₂, thu được N₂, CO₂ và 0,4 mol H₂O. Mặt khác, cho 0,1 mol E tác dụng hết với dung dịch NaOH, cô cạn dung dịch sau phản ứng, thu được hỗn hợp hai chất khí đều làm xanh quỳ tím ẩm và a gam hỗn hợp hai muối khan. Giá trị của a là 

A. 11,60

B. 9,44

C. 11,32

D. 10,76

Ở một loài sinh vật lưỡng bội, cho biết mỗi cặp NST tương đồng gồm 2 chiếc có cấu trúc khác nhau. Trong quá trình giảm phân, ở giới cái không xảy ra đột biến mà có 1 cặp xảy ra trao đổi chéo tại một điểm nhất định, 1 cặp trao đổi chéo tại 2 điểm đồng thời; còn giới đực không xảy ra trao đổi chéo. Quá trình ngẫu phối đã tạo ra 2²¹ kiểu tổ hợp giao tử. Bộ NST lưỡng bội của loài này là:

A. 2n = 14

B. 2n = 16

C. 2n = 18

D. 2n = 20

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Tên :Nguyễn Ngọc Lê
Link : /id/91038

Rewrite

Her hair is long. It is black and straight.

=> She has a long straight black hair

Cycle the best answer

1. Do you want ...... some photos for you?

A. I take B. me take C.me taking D.me to take

2. ...... your new classmate? - Yes, she is very nice.

A.Do you like B.Do you want C.Would you like D.How is

3. How .......kilos of rice do you want?

A. many B.much

4. What time ...... on television?

A.is the film B. are the film C.is film D.are films

5. ........ weekends he usually goes fishing

A. in B.for C.on D.at

2/3        

Rewrite the sentnces with the words given :

1. How many rooms are there in his house ? (have)
=> How many rooms does his house have ?

2. That apartment is more modern than any apartments. (That ....)
=> That apartment is the most modern

3. No apartment here is more expensive than that apartment. (That apartment ....)

=> That apartment is the most expensive

4. The break lasts fifteen minutes (I have ....)
=> I have a fifteen-minute breakfast

5. His interest is English. (He is ....)
=> He is interested in English

6. They take part in outdoor activities (participate)
=> They participate in outdoor activities

7. I would rather stay at home (prefer)
=> I would prefer to stay at home

8. He collects stamps (He is ....)
=> He is fond of collecting stamps

9. Collecting comics is easy (It's ....)
=> It's easy to collect comics

10. It's difficult for me to learn English (difficulty)
=> Learning English is my difficlulty

11. I find math difficult (It's ....)
=> It is difficult for me to study Math

12. I am going to buy a new school bag tomorrow (I intend)
=> I intend to buy a new school bag tomorrow

13. It takes me about five minutes to go to school by bike (spend)
=> I spend five minutes going to school by bike

14. It often takes him two hours to do his homework (He)
=> He spends two hours doing his homework

15. Mr. Hung sometimes travels to work by plane (fly)
=>Mr Hung sometimes flies to work

16. They never go to school late (They are ....)
=> They are go to school on time

17. Listening to music at home is more interesting than going to the concert (I prefer ....)
=> I prefer listening to music to going to the concert

18. Nam is taller than Bac. Bac is taller than Trung. (Of the three, Nam ....)
=> Of the three, Nam is the tallest .

19. We like listening to music more than playing chess (prefer)
=> We prefer listening to music to playing chess

dùng từ gợi ý viết thành câu hoàn chỉnh

- the students/ like/ read/ scientific books /library
=> The students like reading book scientific books in the library

- mr.brown / often/ give/ advice/ his students

=> Mr.Brown often gives some advice for his students

-the girls/ have/ learn/ how/ make/ cakes
=> The girls have learned how to make cakes

-she/ at school/ now/ she/ teach/ english/ my class
=> She is at school, she is teaching my class English now.

- it/ easy/find/ book/ either/ author/ title
=> It is easy to find a book either an author or a title

tìm và sửa lỗi sai trong câu sau

1. Remember to wash and ironing your own clothes every day.
=> ironing --> iron

2. They often go to bed early and never get up lately.
=> lately--> late

3. To keep fit and stay healthily, you should exercise regularly.
=> healthily-- > healthy

4. It's getting easier for me to write and I make mistake.
=> I make mistake --> make mistakes

5. Play football is one of the most common ways of relaxing.

=> Play-- >Playing

6. John doesn't work so hardly as Peter, but he is much more careful than Peter.
=> hardly --> hard

7. Each student studying chemistry have to spend at least three hours per week in the laboratory.
=> have --> has

8. The most problematical of the four major language skills are probably that of writing.
=> are --> is

9. She wants to go to Ho Chi Minh City to begin her carees like a singer.
=> like --> as

10. Please arrive early so that we can start the meeting at time.
=> at time --> on time

Viết lại câu giữ nguyên nghĩa:

1.The red clock is newer than blue clock

=> The blue clock isn't as new as the red clock

2.No moutain in higher than Phanxipang.

=> Phanxipang is the highest mountain

3.Oxford Street is longer than Sydney Street

=> Sydney Street isn't as long as Oxford Street

4.Micheal is faster than his brother

=> Micheal's brother isn't as fast as Micheal

5.The winter is the coldest season.

=> No season is colder than the winter.

3^3 + 3 = 30

1^3 + 1 = 2

2^3 + 2 = 10

4^3 + 4 = 68