: Định m để 2 p/t tương đương: x – 4 = 0 và (m – 1)x + 5 = 2m – x

Viết số thập phân thích hợp vào chỗ chấm: a) 5 m2 675dm2=......m2 1996dm2=....m2 2m 82dm=...m 65dm=.m b) 4dm2 97cm2=...dm2 5dm2 6cm2 =..dm2 2030cm =......dm 105 cm = dm giúp mình vói mình dg cần gấp

Bài 1: Tính hợp lí 1/ (-37) + 14 + 26 + 37 2/ (-24) + 6 + 10 + 24 3/ 15 + 23 + (-25) + (-23) 4/ 60 + 33 + (-50) + (-33) Bài 2: Bỏ ngoặc rồi tính 1/ -7264 + (1543 + 7264) 2/ (144 – 97) – 144 3/ (-145) – (18 – 145) 4/ 111 + (-11 + 27) Bài 3: Tính tổng các số nguyên x biết: 1/ -20 < x < 21 2/ -18 ≤ x ≤ 17 Bài 4: Tính giá trị của biểu thức 1/ x + 8 – x – 22 với x = 2010 2/ - x – a + 12 + a với x = - 98 ; a = 99 Bài 5:. Tính nhanh. 1) 2004 + [ 520 + (-2004)] 2) [(-851) + 5924] + [(-5924) + 851]

tính giá trị biểu thức a) a=2+5+8+11+...+2012 b) b=(1- 1/2).(1- 1/3).(1- 1/4)....(1- 1/2011).(1- 1/2012)

I. Choose the best option to complete each of the following sentences. 1. John said he _______ boxing because it _______ a cruel sport. A. doesn’t like/ is B. did not like / were C. not liked / had been D. had not liked / was 2. Andrew told me that they _______ fish the previous day. A. have not eaten B. had eaten C. did not eat D. would not eat 3. Jackson told me that he _______ his best in the exam the following day. A. had done B. will do C. would do D. was going 4. She asked me_______________I liked pop music. A. if B. when C. that D. how 5. Peter asked Jane why__________ the film on T.V the night before. A. didn’t she watch B. hadn’t she watched C. she doesn’t watch D. she hadn’t watched 6. Julia said that she ___________ there at noon the next day. A. is going to be B. was going to be C. will be D. can be 7. He _______ that he was leaving that afternoon. A. told me B. told to me C. said me D. says to me 8. My parents reminded me ________ the flowers. A. planted B.to plant C. plant D. planting 9. He asked me _______ Robert and I said I did not know _______. A. that did I know / who were he B. that I knew / who he had been C. if I knew/ who he was D. whether I knew / who had he been 10. His father _________ him to take a Chinese course during the summer holiday. A. said to B. suggested C. advised D. recommended 11. My mom said that if she ________younger, she _________ a lot. A. is – will travel B. were- would travel C. had been – would have travelled D. was – will travel 12. Laura said that when she_________ to school, she saw an accident. A. was walking B. has walked C. had been walking D. has been walking 13. Peter___________ of a big house and a BMW car. A.believed B. accused C. dreamed D. suggested 14. The guest told the host that _______. A. I must go now B. he must go then C. he had to go now D. he had to go then 15. I asked Martha ______ to enter law school. A.whether was she planning B. if is she planning C. if she was planning D. whethet you are planning 16. They said that they had been driving through the desert__________. A. the previous day B. yesterday C. the last day D.Sunday previously 17. He asked the children _________too much noise. A. not to make B. not making C. don’t make D. if they don’t make 18. Laura said she had worked on the assignment since _______. A. yesterday B. two days ago C. the day before D. the next day 19. John said he _________ her since they ________ school. A. hasn’t met–left B. hadn’t met-had left C. hadn’t met/ left D. didn’tmeet – left 20. The scientist said the earth ________ the sun. A. goes round B. is going around C. went around D. was going around

biet 1^3+2^3+3^3...+10^3=3025 Tinh 2^3+4^3+6^3...+20^3

Câu 1. Trình bày đặc điểm chung của lớp cá? Câu 2. Cho những ví dụ về ảnh hưởng của điều kiện sống khác nhau đến cấu tạo cơ thể và tập tính của cá?

tính giá trị biểu thức a. [ 128,4 - 73,2 ] : 2,4 - 18,32 b. 8,64 : [1,46 + 3,34 ] + 6,32

4/ Cuộn sơ cấp của một máy biến thế có 400 vòng, cuộn thứ cấp có 240 vòng. Khi đặt vào hai đầu cuộn sơ cấp một hiệu điện thế xoay chiều 220V thì ở hai đầu dây của cuộn thứ cấp có hiệu điện thế là bao nhiêu?

mn giúp mk bài này vs đc ko ạ mk cảm ơn một người đi xe đạp trên đoạn đường MN.Nửa đoạn đường đầu người ấy đi được với vận tốc v1=20km/h.Trong nửa thời gian của nửa đoạn đường còn lại đi với vận tốc v2=10km/h.Cuối cùng người ấy đi với vận tốc v3=5km/h.Tính vận tốc trung bình trên cả đoạn đường MN.