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Đáp án là A

4. Rewrite the sentences using the impersonal passive.

1. It is said that Christopher Columbus discovered America.

→ Christopher Columbus is said      to have  discovered America.

2. It is reported that many people become homeless after the flood.

→ Many people are reported to  become homeless after the flood.

3. It is expected that the Prime Minister will pass the new law.

→ The Prime Minister is expected to pass the new law.

4. It was expected that the Mr. Sarkozy would lose the second presidential election.

→ Mr. Sarkozy was expected to have been able to lose the second presidential election.

5. It is believed that the thieves got in through the unlocked window.

→ The thieves are believed to have got in through the unlocked window.

6. It is found that she exceeded the speed limit.

→ She   was found to have exceeded the speed limit.

7. It is reported that 3 people were badly hurt in the accident.

→ Three people are reported to have been badly hurt in the accident.

8. It is reported that three suspects were arrested after the bomb attack.

→ Three suspects are reported to have been arrested after the bomb attack.

9. It is thought that the prisoner escaped by climbing over the wall.

→ The prisoner       is thought to have escaped by climbing over the wall.

10. It is reported that the wanted man is hiding in a small house in the suburb.

→ The wanted man           is reported to be hiding in a small house in the suburb.

1. Christopher Columbus is said to have discovered America .

2. Many people are reported to become homeless after the flood .

3. The Prime Minister is expected to pass the new law .

4. The Mr. Sarkozy was expected to have lost the second presidential .

5. The thieves are believed to have got in through the unlocked window .

6. She is found to have exceeded the speed limit .

7. Three people are reported to have been badly hurt in the accident .

8. Three suspects are reported to have been arrested after the bomb attack .

9. The prisoner is thought to have escaped by climbing over the wall .

10. The wanted man is reported to hide in a small house in the suburb .

khoảng cách mặt trời trái đất là s= 149,6 .10⁶ km

vận tốc ánh sáng c= 300 000 km/s

=> thời gian t=s/v = 498,67s = khoảng 8,3 phút

8 phút 19 giây

Bài giải

Thời gian đi từ A đến B gấp 3 lần thời gian đi từ B đến C nên nếu coi thời gian đi từ B đến C là 1 phần thì thời gian đi từ A đến B là 3 phần như thế.Mà tổng thời gian đi từ A đến C là 8 giờ nên thời gian đi quãng đường BC:

                                     8 : (3+1)=2 (giờ)

Thời gian đi quãng đường AB:

                                     2 x 3=6(giờ)

Nếu đi từ B đến C với vận tốc cũ thì sau 2 h ô tô chỉ tới đc D và cách C:

                                    5 x 2 = 10 (km)

Đoạn đường AB dài hơn BD là:

                                    130 + 10 = 140 (km)

Trong :6-2=4(giờ),ô tô đi đc 140 km.

8h ô tô đi được:

                                    140 x 2= 280(km)

Quãng đường AC dài:

                                    280 + 10 + 290(km)

                                                                                   Đáp số:290 km

2 giờ 10 phút

Đáp án: was discovered

1.Một sản phẩm làm trong 3 giờ 15 phút = 195 phút.

Tám sản phẩm làm trong :

8 × 195 = 1560 (phút) = 26 (giờ)

1.Một sản phẩm làm trong 3 giờ 15 phút = 195 phút.

Tám sản phẩm làm trong :

8 × 195 = 1560 (phút) = 26 (giờ)

1.It's said that Christopher Columbus discovered America.

 Christopher Columbus is said………to have discovered America…………………….

2.It is said that many people are homeless because of the flood

many people……are said to be homeless because of the flood…………………………………………….

3.It is known that the Prime Minister is in favor of the new law.

The Prime Minister……is known to be in favor of the new law………………………………………

4.It is expected that the US President will lose the election.

The US President …is expected to lose the election…………………………………………

 5. It is believed that the thieves got in through the kitchen window .

The thieves ……are believed to have got in through the kitchen window……………………………………………………

6. It is found that she drove through the town at 50 miles an hour.

She ……is found to have driven through the town at 50 miles an hour………………………………………………………..

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

 Tow people…are reported to have been seriously injured in the accident………………………………………………………..

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

Three men……are said to have been arrested after the explosion…………………………………………….

9.It is thought that the prisoner escaped by climbing over the wall

The prisoner……is thought to have escaped by climbing over the wall………………………………………………….

10.It is believed that the wanted mam is living in New York

The wanted man…is believed to be living in New York………………………………………..