Thế nào là lực đàn hồi ? Nêu đặc điểm của lực đàn hồi ? Cho ví dụ

Ex: complete the sentences with the correet form of the adjectives in brackets 1. It's a .......... book and I'm .............every time I start reading it. (bore) 2. I was very .......in the lesson because out teacher is very ...........in history.(interest) 3. We were all very .........about the school trip but it wasn't an.............trip at all.(excite) 4. Studying for exams is very ............I get ...........when I open my school books.(tire) 5. My friend is a very ..........sort of person but he hates doing ........ activities.(relax)

Combine these pairs of sentences, using adverbial clauses of purpose. 1. He went to the bookstore. He wanted to pass the exam.  2. I’ll give you my address. I want you to be able to come with me.  3. The teacher spoke very slowly. He wanted his students to understand what he said.  4. She sent her children to their house. She wanted to have some peace.  5. Her parents sent her to Canada. They wanted her to study economics there.  6. My sister is learning Chinese. She wants to get a good job.  7. The children get up early. They want to do morning exercises.  8. Loan telephoned me. She wanted to invite me to her birthday party.  9. Trinh went shopping early in the morning. She wanted to buy something.  10. Hoa goes to the post office. She wants to buy some stamps.  11. Mr. Pike is learning Vienamese. He wishes to read Kim Van Kieu.  12. Please shut the windows and the door. I don’t want the cat to go into the house.  13. The man built a high wall around his garden. The fruit wouldn’t be stolen.  14. The policeman stopped the traffic every few minutes. The pedestrians might cross the road.  15. The notices are written in several languages. Everyone may understand them.  16. The little girl stood on the chair. She could see the show better.  17. He wishes he had enough money. He wants to buy a new house.  18. Britney is practicing the piano. She can play for the dance.  19. I need a job. I want to support my old teacher.  20. We moved to the front row. We could hear the speaker better. 

Y^2=1+căn9-x^2-4x tim x y làm hộ

Từ nội dung đoạn trích ở phần Đọc hiểu, anh/ chị hãy viết 01 đoạn văn (khoảng 200 chữ) để khuyên mọi người hãy biết vui sống. mọi người giúp mình với, mình cảm ơn :)))))

Mn làm giúp mình phần đọc hiểu với ạ

Phương trình nào dưới đay là phương trình bậc nhất một ẩn A.ox+1=0. B. x mũ 2 × x= 0. C. 2 phần x - 1 = 0. D. 1 - 2x = 0

giải hộ mình với Mình cảm ơn <3

2(x+7)=-16 |x-9|=7 (x-5)(x+7)=0 a)-3<x<2 b)-2011<x<2011 giúp với

mọi người giải giúp em bài này vs ạ