trong chọn giống vạt nuôi,chủ yếu người ta thường dùng phương pháp nào ?Tại sao?cho ví dụ

6,72 khí CO2 (đktc) tác dụng vừa hết với 600 ml dd Ba(OH)2,sản phẩm tạo thành là BaCO3 và nước.

a.Viết PTHH

b.Tính nồng độ mol của dd BaOH đã dùng

c.Tính khối lượng kết tủa tạo thành

Read the passage carefully and choose the correct answer.

Almost every language in the world has dialects and American English is no exception. At the present time there is an interesting study which is on American speech habits. This study has shown that different words are frequently used in different parts of the country to denote the same thing. For example, in the east, Americans use the word "soda" to denote a soft drink. In some parts of the west, a soft drink is "tonic". Such differences are usually a source of conversation and sometimes misunderstanding happens.

Speech and life all over the world have often changed. New words are being used when new discoveries are made and new concepts are formed. Usage determines what is correct and what is incorrect. Fifty years ago, it was incorrect to say "It's me." But today it is acceptable simply because most Americans say that instead of "It's I." People change, so language changes. What is wrong today may be right tomorrow.

36. Which sentence is true?
A. American English has no dialects. B. American English has dialects.
C. There is no study on American speech habits. D. American English- has no exception.

37. The study has shown that ______
A. different words are used in different parts to denote the same thing
B. different words are used in different parts to denote a different thing
C. there are no different words in different parts
D. dialects do not exist in American English

38. Differences in speech can lead to ______
A. dialects B. changes C. new concepts D. misunderstanding

39. What determines whether a word is correct or incorrect?
A. change B. usage C. dialect D. study

40. Language ______
A. frequently changes B. is the same in almost every part
C. makes misunderstanding happen D. makes people change

1.Word Formations:

1.I have never been..............................like that before (threat)

2.There is a saying in English :''.......................speak louder than words .''(act)

3.That rules is not ..........................in this case .(apply)

4.Tom eyes are...............................because he hasn't got enough sleep .(blood)

5.English is a..........................easy language for Swedes to learn .(compare)

6.Now,don't tell anyone else what I've just told you .It's ...............................(confide)

7.The recent hurricane caused ............................... damage .(wide)

8.Industrial robots workwith far greater...............................than most men .(precise)

9.The Army tried to .......................................the goverment .(throw)

10.There was a .................................yesterday afternoon which ruined the party .(pour)

11.Although the splitting of the atom was one of the greatest scientific .................................of this century,there are many peoplewho wish it had never happened.(break)

12.The new ............................... in that city makes traveling to Hanoi easier and faster .(pass)

13.He was born blind ,but despite this......................................he managed to become one of the top Pop singers of his generation.(able)

14.I think he is ...........................to cut down the salary during this situation.(reason)

15.The lovers stood ,hand in hand ,gazing at the ...............................sky .(star)

16.He won the discus event at the Olympic Games but was later ...........................when a medical check proved that he had been taking drugs.(qualify)

17.He was very.....................when the result of was announced.(set)

18.There hasbeen a severe.............................of cholera in Congo.(break)

19.Some people claim to be able to..............................the future .(tell)

Find the word which has a different sound in the part underlined.
1. A. listened B. stayed C. opened D. wanted
2. A. frustrated B. relaxed C. embaassed D. depressed

3. A. multicultural B. conduct C. stuck D. fabulous
4. A. what B. where C. whole D. why
5. A. meat B. reading C. bread D. seat
6. A. writes B. makes C. takes D. drives
7. A. never B. often C. when D. tennis
8. A. needed B. watched C. stopped D. talked
9. A. ethic B. thanks C. these D. birthday
10. A. open B. doing C. going D. cold
11. A. out B. round C. about D. would
12. A. listened B. stayed C. wanted D. played
13. A. humor B. history C. hour D. hoy
14. A. there B. thank C. thirsty D. youth
15. A. clothes B. matches C. colleges D. churches
16. A. worked B. naked C. liked D. looked
17. A. sunbathe B. father C. theater D. weather
18. A. option B. information C. question D. invitation
19. A. stamps B. rulers C. cats D. books
20. A. try B. my C. sky D. study
21. A. sound B. round C. about D. could

22. A. fixed B. watched C. missed D. played
23. A. humor B. history C. honest D. hoy
24. A. they B. thank C. thirsty D. youth
25. A. clothes B. washes C. changes D. watches
26. A.watched B. stayed C. liked D. looked

27. A. these B. father C. theater D. weather
28. A. nation B. information C. question D. pollution
29. A. stamps B. plays C. wants D. books
30. A. decided B. played C. wanted D. provided
31. A. city B. cathedral C. central D. cinema
32. A. treat B. clean C. great D. beach
33. A. clean B. cook C. celeate D. candy
34. A. spring B. visit C. present D. season
35. A. chat B. teacher C. chocolate D. chemistry

Question I. Find the word which has different sound in the part underlined.

1. A. what B. where C. whole D. why

2. A. out B. round C. about D. would

3. A. listened B. stayed C. wanted D. played

4. A. humor B. history C. hour D. hobby

5. A. worked B. naked C. liked D. looked

Question II. Find the word which has different stress pattern from the others.

1.A. person B. father C. teacher D. enjoy

2. A. happen B. enjoy C. destroy D. agree

3.A. advise B. permit C. picture D. expect

4.A. erupt B. visit C. listen D. open

5.A. depend B. advise C. affect D. listen

1.A.what B.where C.whole D.why

2.A.out B.round C.about D.would

3.A.listened B.stayed C.wanted D.played

4.A.humor B.history C.hour D.hobby

5.A.worked B.naked C.liked D.looked

1. If we (recycle) _____ more, we will help the Earth.

2. Factories (not dump) _____ waste into rivers if the government fines them heavily.

3. Students will be more aware of protecting environment if teachers _____ (teach) environmental issues at school.

4. If light pollution ______ (happen), animals will change their behaviour patterns.

5. If people (travel) _____ to work by bus, there will be fewer car fumes.

6. We _____ (save) thousands of trees if we don’t waste paper.

7. If we use water carefully, more people _____ (have) fresh water.

8. The level of radioactive pollution will decrease if we _____ (switch) from nuclear power to renewable energy sources.

9. If the water temperature (increase) _____, some aquatic creatures will be unable to reproduce.

10. People will get more diseases if the water (be) _____ contaminated.

11. If you (be) _____ the president, what would you do to help the environment?

12. They get sick so often. If they (exercise) _____ more, they (be) _____ healtheir.

13. If I had one million US dollars, I (build) _____ more parks in our city.

14. Ngoc’s mother is unhappy. If Ngoc (tidy) _____ her room everyday, her mother (not be) _____ so upset.

15. There isn’t a garden at our house. If there (be) _____, we (grow) _____ vegetables.

16. It (not be) _____ possible to save the Earth if we don’t take action now.

17. If the world temperatures continue to rise, there (be) _____ less snow.

18. If I (be) _____ you, I would wear earplugs when going to the concert.

19. If we do nothing to stop global warming, we (see) _____ big changes in the future.

20. How _____ you _____ (travel) to work if you didn’t have this motorbike?

21. Our garden is so beautiful. There (not be) _____ any flowers if my sister (not take care) _____ it every day.

22. If pigs (have) _____ wings, _____ (they/be able) to fly?

23. If I _____ (be) an astronaut, I _____ (travel) to other planets.

24. If you _____ (not see) Tom ever again, how _____ (you/feel)?

25. What _____ (you/do) if you _____ (see) a ghost?

26. If you _____ (eat) more of this cake, you _____ (be) sick. You’ve already had five slices!

27. Who _____ (you/vote) for if you _____ (be) eighteen?

28. If you _____ (be) late, we _____ (not wait). We’ll have to go without you!

29. If the ozone layer is not protected, we _____ (suffer) from excessive ultraviolet radioation.

30. If you _____ (leave) the lights that you are not using on, you’ll cause over-illumination, a form of light pollution.

31. Soil pollution _____ a serious problem to solve if levels of pollutants in soil go beyond what should be naturally allowed.(be)

32. If your farming land _____ near a landfill or an industrial area, it is essential that you test the soil for pollutants before growing anything adible. (be)

33. You will be less likely to suffer lung cancer if you _____. (not smoke)

34. If it is sunny, we _____ a clean-up of the garden. (do)

35. If local residents _____ cutting trees for wood at this rate, the forest will soon be gone. (keep)

36. If we take good care of the garden, we _____ flowers all year round. (have)

37. If man _____ dumping waste into the sea, they will soon be victims. (keep)

38. We’ll go without Linh if she _____. (not come)

39. If everyone _____ a small contribution, we’ll be able to do a good cause. (make)