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2 tháng 3

Coi thể tích của bể là 1 đơn vị.

1 giờ vòi thứ nhất chảy được:

     1:6=\(\dfrac{1}{6}\) (bể)

1 giờ vòi thứ hai chảy được:

     1:8=\(\dfrac{1}{8}\) (bể)

Đổi: 1 giờ 15 phút = \(\dfrac{5}{4}\) giờ

1 giờ 15 phút vòi thứ nhất chảy được:

     \(\dfrac{1}{6}\cdot\dfrac{5}{4}=\dfrac{5}{24}\) (bể)

Số phần bể chưa có nước là:

     \(1-\dfrac{5}{24}=\dfrac{19}{24}\) (bể)

1 giờ cả hai vòi chảy đươc:

     \(\dfrac{1}{6}+\dfrac{1}{8}=\dfrac{7}{24}\) (bể)

2 vòi chảy trong thời gian là:

     \(\dfrac{19}{24}:\dfrac{7}{24}=\dfrac{19}{7}\) (giờ)

Vậy cả hai vòi chảy trong \(\dfrac{19}{7}\) giờ.

2 tháng 3

Cảm ơn bạn Nguyễn Quang Tâm nhé! 

2 tháng 3

-Thực vật không có mạch :

+Cơ thể không có mạch dẫn

+Rễ giả

-Thực vật có mạch:

+ Cơ thể có mạch dẫn

+Có thân,rễ thật,lá

Có mạch dẫn,rễ thật là thực vật có mạch

Không có mạch dẫn,rễ thật là thực vật không có mạch.

2 tháng 3

-Thực vật không có mạch :

+Cơ thể không có mạch dẫn

+Rễ giả

-Thực vật có mạch:

+ Cơ thể có mạch dẫn

+Có thân,rễ thật,lá

3 tháng 3

1. These are ________brightly______coloured flowers. BRIGHT

 

2. Repeated use of some washing powders can lead to a loss of_____brightness_________in colours.

 

BRIGHT

 

3. She gave the greatest _______performance_______of her career. PERFORM

 

4. By the age of 15, Allan had become an experienced circus _____performer_________.PERFORM

 

5. Ms. Mai spoke very ____powerful__________about that yesterday. POWER

 

6. We follow very strict guidelines on the use and______storage________of personal details on

 

computers. STORE

 

7. The astronauts are _______weightless_______in space. WEIGHT

 

8. After nearly five months of ______weightlessness________, the astronauts of the international space

 

station said they were happy to return to Earth. WEIGHT

 

9. Follow the instructions on the back of the bag ______carefully________. CARE

 

10. He drove _________carelessly_____and caused a serious accident. CARE4

sossssssssssssssssssssss

 

2 tháng 3

cái này là nói hay tìm hình ảnh xong gửi cho giáo viên vậy bạn?

 

1. There're 2 main kinds of  sports in the world.

2. No, it isn't.

3. Yes, they do.

4. The two separate teams compete against each other to get the best score.

5. Team sports are sometimes called competitive sports.

Học tốt nhó ^^

3 tháng 3

1 There are two main kinds of sports in the world

2 No, it isn't

3 Yes, they do

4 They compete against each other in order to get the best score

5 They are sometimes called competitive sports

                    TELEVISION Television is an (1) _______ invention of the 20th century. It has been so popular that now we can’t imagine what life would be if (2)______ were no television. Television is a major means of communication. It (3)______ pictures and sounds from around the world into millions of home. Though television viewers can see (4)_____ learn about people, places and things in far away lands, television widens our knowledge by introducing (5) _____to new...
Đọc tiếp

 

 

                TELEVISION

Television is an (1) _______ invention of the 20th century. It has been so popular that now we can’t imagine what life would be if (2)______ were no television. Television is a major means of communication. It (3)______ pictures and sounds from around the world into millions of home. Though television viewers can see (4)_____ learn about people, places and things in far away lands, television widens our knowledge by introducing (5) _____to new ideas which may lead us to new hobbies and recreations. In addition to the news, television provides us with (6)_____ variety of programs that can satisfy every (7) _______. Most people now seem to like spending their evenings (8)______ television.  It is (9)_____ convenient for them to sit at home watching television than go out (10) ______  amusements elsewhere.

 1.  A. important

 2.  A. there

 3.  A. gets

 4.  A. but

 5.  A. us

 6.  A. a

 7.  A. tasted

 8.  A. watching

 9.  A. most

10.  A. with

B. more important

B. those

B. brings

B. so

B. we

B. an

B. tastes

B. looking

B. many

B. to

C. importance

C. these

C. gives

C. and

C. our

C. the

C. tasty

C. seeing

C. much

C. at

D. unimportant

D. they

D. shows

D. however

D. ours

D. X

D. taste

D. cleaning

D. more

D. for

1
3 tháng 3

1 A

2 A

3 B

4 C

5 A

6 A

7 D

8 A

9 D

10 A

SYDNEY Sydney is Australia’s most exciting city. The history of Australia begins here. In 1788 Captain Arthur Philips arrived in Sydney with 11 ships and 1624 passengers from Britain (including 770 prisoners). Today there are about 3.6 million people in Sydney. It is the biggest city in Australia, the busiest port in the South Pacific and one of the most beautiful cities in the world. In Sydney, the buildings are higher, the colors are brighter and the nightlife is more exciting. There are...
Đọc tiếp

SYDNEY

Sydney is Australia’s most exciting city. The history of Australia begins here. In 1788 Captain Arthur Philips arrived in Sydney with 11 ships and 1624 passengers from Britain (including 770 prisoners). Today there are about 3.6 million people in Sydney. It is the biggest city in Australia, the busiest port in the South Pacific and one of the most beautiful cities in the world. In Sydney, the buildings are higher, the colors are brighter and the nightlife is more exciting. There are more than twenty excellent beaches close to Sydney and its warm climate and cool winter have made it a favorite city for immigrants from overseas. There are two things that make Sydney famous: its beautiful harbor, the Sydney Harbor Bridge, which was built in 1932 and the Sydney Opera House, which was opened in 1973.

1. Which of the following should be the title of the reading passage?

A. Sydney’s Opera House                                 B. The history of Sydney

C. Sydney’s beaches and harbors                       D. An introduction of Sydney

2. Where does history of Australia begin?

A. South Pacific      B. Sydney Harbor              C. Britain                D. Sydney

3. Which of the following statements is NOT true about Sydney?

A. Immigrants from overseas do not like Sydney.

B. Sydney is one of the most charming cities in the world.

C. Sydney is the most interesting city in Australia.

D. Sydney is the busiest port in the South Pacific.

4. How many beaches are there close to Sydney?

A. almost 20 beaches                                       B. over 20 beaches           

C. nearly 20 beaches                                         D. exactly 20 beaches

5. What is the population of Sydney?

A. 1624 passengers                                            B. about 3.6 million people            

C. 770 prisoners                                                D. 11 ships

3
2 tháng 3

@_@ ?

thằng nghĩa nhá bắt quả tang

Question 7. Write the correct form of each bracketed word in the numbered space provided below. (1.0 pt) 1. If he _____ hard, he will pass the examination.                                               (STUDENT)   2. This chair is _____ , so my mother dislikes sitting on it.                                (COMFORT) 3. I am Vietnamese. What is your _____ ?                                                              (NATION)   4. We must be _____ when we cross the board.           ...
Đọc tiếp

Question 7. Write the correct form of each bracketed word in the numbered space provided below. (1.0 pt)

1. If he _____ hard, he will pass the examination.                                               (STUDENT)  

2. This chair is _____ , so my mother dislikes sitting on it.                                (COMFORT)

3. I am Vietnamese. What is your _____ ?                                                              (NATION)  

4. We must be _____ when we cross the board.                                                           (CARE) 

5. My house is on the _____ floor of that tall building.                                                (NINE) 

6. This tree has a lot of green _____.                                                                             (LEAF)                          

7. They are going to _____ for the Christmas.                                               DECORATION) 

8. Minh is _____ at English than I am                                                                            (BAD)

9. It may not be easy to change your lifestyle _____.                                        (COMPLETE)  

10. There is a _____ between the two pictures.                                                 (DIFFERENT)

1
3 tháng 3

1 studies

2 uncomfortable

3 nationality

4 careful

5 ninth

6 leaves

7 decorate

8 worse

9 completely

10 difference

2 tháng 3

Bài `1`:

`a.` Rút gọn:

`21/35 = (21 : 7)/(35 : 7) = 3/5`

`=> BCNN(5,-25) = 25`.

`=> 3/5 = (3 * 5)/(5 * 5) = 15/25`

`=> 13/-25 = (13 * (-1) )/( (-25) * (-1) ) = (-13)/25`

`b.` `BCNN(5,-12,6) = 60.`

`=>` `2/5 = (2 * 12)/(5 * 12) = 24/60.`

`=>` `3/-12 = (3 * (-5) )/( (-12) * (-5) ) = (-15)/60`

`=>` `5/6 = (5 * 10)/(6 * 10) = 50/60`

2 tháng 3

\(\dfrac{-12}{-15}=\dfrac{x}{25}\)

\(\dfrac{12}{15}=\dfrac{x}{25}\)

\(x\cdot15=12\cdot25\)

\(x\cdot15=300\)

\(x=300:15\)

\(x=20\)

AH
Akai Haruma
Giáo viên
3 tháng 3

Lời giải:
$\frac{1}{4^2}+\frac{1}{5^2}+\frac{1}{6^2}+...+\frac{1}{100^2}$

$< \frac{1}{3.4}+\frac{1}{4.5}+\frac{1}{5.6}+...+\frac{1}{99.100}$

$=\frac{4-3}{3.4}+\frac{5-4}{4.5}+\frac{6-5}{5.6}+...+\frac{100-99}{99.100}$

$=\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+\frac{1}{5}-\frac{1}{6}+...+\frac{1}{99}-\frac{1}{100}$

$=\frac{1}{3}-\frac{1}{100}< \frac{1}{3}$