Vẽ sơ đồ lắp đặt mạch điện gồm các thiết bị điện sau: Cầu chì, 2 bóng đèn huỳnh quang, 2 công tắc điều khiển bóng đèn, 2 quạt trần, 2 công tắc điều khiển quạt trần, 1 ổ điện

a) Xét \(\Delta ABE\) và \(\Delta ACF\) có:

\(\widehat{AEB}=\widehat{AFC}\)

\(\widehat{A}\) chung

\(\Rightarrow\Delta ABE\sim\Delta ACF\left(gn\right)\)

b) Vì \(\Delta ABE\sim\Delta ACF\)

\(\Rightarrow\widehat{ABE}=\widehat{ACF}\left(1\right)\)

Theo bài ra, ta có: AB // d

\(\Rightarrow\widehat{ABE}=\widehat{BED}\left(2\right)\)

Từ (1) và (2)

\(\Rightarrow\widehat{ACF}=\widehat{BED}\)

Xét \(\Delta HED\) và \(\Delta HEC\) có:

\(\widehat{BED}=\widehat{ACF}\)

\(\widehat{EHC}\) chung

\(\Rightarrow\Delta HED\sim\Delta HEC\left(g-g\right)\)

\(\Rightarrow\dfrac{HE}{HD}=\dfrac{HC}{HE}\)

\(\Leftrightarrow HE^2=HD.HC\)

1. suitable

2. appropriation

3. expression

4. technical

5. telepathic

1. John asked Mary how long it took her to get to London.

2. The policeman asked the little girl what her name was

3. Mr. Green asked his secretary who she had talked to a few minutes before

4. She asked her son if he knew which was the cup he used

5. Helen asked Jack what he had said

6. Dr. Nelson said that the astronauts could have private video conferences with their families on the Earth every weekend

7. Nick asked his teacher if the astronauts had ever forgotten anything from the Earth

8. The teacher told Nick that the astronauts on the ISS used a 3-D printer on board to print certain objects

9. The teacher said that Ganymede, the largest moon of Jupiter, had a large salt water ocean

Reading books is an useful activity in the modern life today.

Write a short paragraph to express your ideas about the benefits of reading (120 - 140 words)

Write a passage about your summer vacation last year

Viết một đoạn văn phân tích nhân vật Lão Hạc, trong đoạn văn có sử dụng câu cảm thán và câu nghi vấn