Một tàu ngầm đang di chuyển ở dưới biển. Áp kế đặt ở ngoài vỏ tàu chỉ áp suất 2,02.10⁶ N/m². Một lúc sau áp kế chỉ 0,86.10⁶ N/m².

a) Tàu đã nổi lên hay đã lặn xuống? Vì sao khẳng định được như vậy ?

b) Tính độ sâu của tàu ngầm ở hai thời điểm trên. Cho biết trọng lượng riêng của nước biển bằng 10300 N/m³.

Hãy so sánh áp suất tại 5 điểm A, B, c, D, E trong một bình đựng chất lỏng vẽ ở hình 8.3.

Complete the sentences with the correct form of the word in brackets.

1.I watch TV every day because it's very.............(inform.)

2.The.....................situation in the country is getting worse and worse.(economy)

3.It's..............of you to cheat in the exam(honest)

4.There are................about wearing uniforms at school.(argue)

5.What is for dinner?It smells very.......(deliciously)

6.I think staying at home all day is................because I don't know what to do.(bore)

7.It is...........to eat a lot of sweeetened foods and drinks.(health)

8.Many people do volunteer work because it can make a........in their community.(differ)

9.Some students usually teach street.........English in the summer.(child)

Choose the word or phrase in brackets that best completes each sentence.

They will burn trash(although/but/because/so).........they want to reduce this amount of garbage.

VI. Read the passage and answer the following questions. (2ps)

Alexander Fleming was born in 1881 in Scotland. He went to a small school in a village, and when he left school he didn't go to university. He worked for five years in an office. But his brother, Tom, was a doctor and helped Fleming to go to university and study medicine. So he went to London University and in 1906 he became a doctor. In 1915, Fleming married Sarah McElroy, an Irish woman. They had one son. During the First World War, many soldiers died in hospital because they didn't have the right medicines. So after the war, Fleming tried to find a drug that could help them. He worked for many years and in 1928 he discovered a new drug and he called it "penicillin". He later worked with an Australian and a German scientist to develop a drug that doctors could use. In 1945, they won the Nobel Prize in medicine for their work on penicillin.

1.How many children did he have?

.......................................................

Read the passage and answer the following questions.(why)

VI. Read the passage and answer the following questions. (2ps)

Alexander Fleming was born in 1881 in Scotland. He went to a small school in a village, and when he left school he didn't go to university. He worked for five years in an office. But his brother, Tom, was a doctor and helped Fleming to go to university and study medicine. So he went to London University and in 1906 he became a doctor. In 1915, Fleming married Sarah McElroy, an Irish woman. They had one son. During the First World War, many soldiers died in hospital because they didn't have the right medicines. So after the war, Fleming tried to find a drug that could help them. He worked for many years and in 1928 he discovered a new drug and he called it "penicillin". He later worked with an Australian and a German scientist to develop a drug that doctors could use. In 1945, they won the Nobel Prize in medicine for their work on penicillin.

1. Where was Alexander Fleming born?

................................................................................................

2. Did he work in an office before he went to university?

...................................................

3. What did he study at university?

...................................................................................................

4. When did he win the Nobel Prize in medicine?

.......................................................................

5.What kind of drug did he discover?

.........................................................................

6.When did he win the Nobel Prize in medicine?

......................................................................................

Rewrite the sentences without changing their meanings.

1.Who cleaned this car this afternoon?(cleaned)

_________________________________________________

2.They said:"We can't talk to her if she doesen't apologise to us for her bad behaviour."

___________________________________________________

3.He has a number of relatives living nearly,but he never visits them(even though)

______________________________________________________

4.Be careful or you'll fall of your bike.

____________________________________________________

5.Our teacher is always a careful driver.(drives)

__________________________________________

6.Mr Tam went to work by car some years ago,but now he cycles.(used)

_________________________________________

7.Road users should obey traffic rules strictly.(obeyed)

___________________________________________________

8.My mother washed clothes by hand in the past,but she no longer does it now.(used)

_________________________________________________________

9.Because Mr Tam was seriously ill last night,he didn't join our party.

_____________________________________________________

10.Despite the rainy wheather tonight,we dicided to go out together.

Although________________________________________

11.They don't have much time.They can't have lunch with us.(enough)

_________________________________________________

12.She practise speaking English everyday.She wants to speak it fluently.(in order to)

_______________________________________________________

13.It is reported that two people were seriously injured in the accident.

Two people_____________________________________

14.It is said that three men were arrested after the explosion.

Three man_________________________________________________

15.They are the best players in this game.

No player____________________________

16.They think that the old man died on the way to the hospital.

It_______________________________

The old man__________________________

17.What a pity you can't take part in our tour.

I wish________________________________

18.The air isn't pure,so were aren't healthy.

If______________________________--

19.We spoke to the man.He was very humorous.(who)

The man_________________________________________

20.His parents are both retired.They now live in Japan.

His parents____________________________

21.They asked me some different questions at the interview.

I___________________________

Rewrite the sentences without changing their meanings.

1.Who cleaned this car this afternoon?(cleaned)

_________________________________________________

2.They said:"We can't talk to her if she doesen't apologise to us for her bad behaviour."

___________________________________________________

3.He has a number of relatives living nearly,but he never visits them(even though)

______________________________________________________

4.Be careful or you'll fall of your bike.

____________________________________________________

5.Our teacher is always a careful driver.(drives)

__________________________________________

6.Mr Tam went to work by car some years ago,but now he cycles.(used)

_________________________________________

7.Road users should obey traffic rules strictly.(obeyed)

___________________________________________________

8.My mother washed clothes by hand in the past,but she no longer does it now.(used)

_________________________________________________________

9.Because Mr Tam was seriously ill last night,he didn't join our party.

_____________________________________________________

10.Despite the rainy wheather tonight,we dicided to go out together.

Although________________________________________

11.They don't have much time.They can't have lunch with us.(enough)

_________________________________________________

12.She practise speaking English everyday.She wants to speak it fluently.(in order to)

_______________________________________________________

13.It is reported that two people were seriously injured in the accident.

Two people_____________________________________

14.It is said that three men were arrested after the explosion.

Three man_________________________________________________

15.They are the best players in this game.

No player____________________________

16.They think that the old man died on the way to the hospital.

It_______________________________

The old man__________________________

17.What a pity you can't take part in our tour.

I wish________________________________

18.The air isn't pure,so were aren't healthy.

If______________________________--

19.We spoke to the man.He was very humorous.(who)

The man_________________________________________

20.His parents are both retired.They now live in Japan.

His parents____________________________

21.They asked me some different questions at the interview.

I___________________________-

Cho hình thang cân ABCD(AB//CD).Gọi E và F lần lượt là trung điểm của các đường chéo BD và AC,G là giao điểm của các đưởng thẳng đi qua E vuông góc với AD và đường thẳng đi qua F vuông góc với BC.

a/Gọi H là trung điểm của CD.CMR:\(HG\perp EF\)

b/CMR:\(EF//CD\)

c/\(\Delta DGC\) là tam giác gì?Vì sao?

Phân tích thành nhân tử các đa thức sau:

\(g/x^2-2xy+y^2-9z\)

\(h/5x^4-20x^2\)

\(i/7x^2-7y^2-14x+14y\)

\(k/x^2+8x+24+3x\)

\(l/x^2+8x+24+3x\)

\(m/x^4-y^4\)

\(n/x^6-y^6\)