D. 74 năm

Thông tin này có trong sách giáo khoa mà bạn

Ta có:\(\left(3\dfrac{3}{4}+\dfrac{4}{7}.\dfrac{7}{16}\right):\dfrac{1}{2}\)

       \(=\left(\dfrac{15}{4}+\dfrac{1}{4}\right).2\)

       \(=\dfrac{16}{4}.2\)

       \(=8\)

Gọi kim loại hoá trị II là A

\(n_{H_2}=\dfrac{4,48}{22,4}=0,2\left(mol\right)\)

\(A+2HCl\xrightarrow[]{}ACl_2+H_2\)

\(0,2\)                                   \(0,2\left(mol\right)\)

\(M_A=\dfrac{4,8}{0,2}=24\left(\dfrac{g}{mol}\right)\)

\(\Rightarrow A\) là \(Mg\)

There is a lot of controversy surrounding the invention __________ (1) the telephone. Of course, Alexander Graham Bell is the father of the telephone. After all it was his design that was first __________ (2), however, he was not the first inventor to come up __________ (3) the idea of a telephone.

Antonio Meucci, an Italian immigrant, began developing the design of a talking telegraph or telephone __________ (4) 1849. In 1871, he filed a caveat (an announcement of an invention) for his design of a talking telegraph. Due to hardships, Meucci could not renew his caveat. His role in the invention of the telephone was overlooked until the United States House of Representatives __________ (5) a Resolution on June 11, 2002, honoring Meucci's contributions and work.

To make matters even more interesting, some researchers suggest that Elisha Gray, a professor at Oberlin College, applied for a caveat of the telephone on __________ (6) same day Bell applied for his patent of the telephone - these gentlemen didn’t actually visit the Patent Office, their lawyers did __________ (7) their behalf. In Historical First Patents: The First United States Patent for Many Everyday Things (Scarecrow Press, 1994), Travis Brown, reports that Bell’s lawyer got to the patent office first. The date was February 14, 1876. He was the fifth entry of that day, ___________ (8) Gray’s lawyer was 39th. Therefore, the U.S. Patent Office ___________ (9) Bell with the first patent for a telephone, US Patent Number 174,465 rather than honor Gray's caveat. _________, (10) some authors dispute this story and suggest that there was malfeasance by certain individuals at Patent Office, and possibly Bell himself.

1. A. of                    B. to                     C. with                      D. for

2. A. to patent                B. to offer             C.invent                 D. to  open

3. A. for               B. on                 C. with                         D. of

4. A. on              B. at                    C. in                         D. of

5. A. pass                 B. passed                C. passing                 D. to pass

6. A. a                     B. x                    C. an                     D. the

7. A. at                     B. on                     C for                        D with

8. A. while                   B. at                  C. therefore                     D. as well

9. A. provided              B. supported         C.objected               D. awarded

10. A. However              

B. Therefore         

C. According to            

D. Addition to

1. They said that John was the brightest student in class.

@ John was said to be the brightest student in class.

2. I will get my hair cut by Jenny tomorrow.

@ I will get Jenny to cut my hair tomorrow. (to)

3. I find it interesting to do volunteer work. 

@  I am interested in doing volunteer work. (interested)

4. They know that Mary won the competition.

@ Mary is known to have won the competition.

5. You need to water these trees every day.

@ These trees need to be watered every day. (watered)

6. The manager should sign these contracts.

@ These contracts should be signed by the manager.

7. No one deleted the files in his computer.

@ The files in his computer weren't deleted.

8. She finds it boring to stay at home all day.                                   

@ She is bored of staying at home all day. (bored)

9. They don’t allow Daisy to go to work on foot.

@ Daisy is allowed to go to work on foot.

10. In the middle of our sleep, a burglar broke in our house.

@ While we were sleeping, a burlar broke in our house.

III/

1. major

2. unemployment

3. responsibility

4. provide

5. equal

6. discouraged

7. Traditionally (thêm dấu phẩy nhé)

8. diverse

9. environmentalist

10. numerous

Choose the word which has underlined letter pronouned differenty from the others

1a.exciting b.spring c.tradition d.swimming

Câu c mình nghĩ là tradition chứ ko phải là trarition